diff --git a/src/main/java/de/ids_mannheim/korap/KrillQuery.java b/src/main/java/de/ids_mannheim/korap/KrillQuery.java
index c966cc0..578d10b 100644
--- a/src/main/java/de/ids_mannheim/korap/KrillQuery.java
+++ b/src/main/java/de/ids_mannheim/korap/KrillQuery.java
@@ -85,10 +85,6 @@
 
     private static final int MAX_CLASS_NUM = 255; // 127;
 
-    // Variables used for relation queries
-    private String direction;
-    private byte[] classNumbers;
-
     // Private class for koral:boundary objects
     private class Boundary {
         public int min, max;
@@ -121,7 +117,6 @@
         };
     };
 
-
     /**
      * Constructs a new object for query deserialization
      * and building. Expects the name of an index field
@@ -133,10 +128,6 @@
      */
     public KrillQuery (String field) {
         this.field = field;
-        this.direction = ">:";
-        this.classNumbers = new byte[2];
-        this.classNumbers[0] = (byte) 1;
-        this.classNumbers[1] = (byte) 2;
     };
 
 
@@ -257,9 +248,6 @@
                     if (number > MAX_CLASS_NUM)
                         throw new QueryException(709,
                                 "Valid class numbers exceeded");
-
-                    this.classNumbers = null;
-
                 }
 
                 // Reference based on spans
@@ -303,12 +291,6 @@
                 // Get wrapped token
                 return this._segFromJson(json.get("wrap"));
 
-            case "koral:relation":
-                if (!json.has("wrap")) {
-                    throw new QueryException(718, "Missing relation term");
-                }
-                return this._termFromJson(json.get("wrap"), direction);
-
             case "koral:span":
                 return this._termFromJson(json);
         };
@@ -446,16 +428,28 @@
 
         SpanQueryWrapper operand1 = fromJson(operands.get(0));
         SpanQueryWrapper operand2 = fromJson(operands.get(1));
-
-        if (operand1.isEmpty()) {
+        
+        String direction = ">:";
+        if (operand1.isEmpty() && !operand2.isEmpty()) {
             direction = "<:";
         }
 
-        SpanQueryWrapper relationWrapper = fromJson(relation);
-
-        return new SpanRelationWrapper(relationWrapper, operand1, operand2,
-                classNumbers);
-
+        if (!relation.has("@type"))
+            throw new QueryException(701,
+                    "JSON-LD group has no @type attribute");
+        
+        if (relation.get("@type").asText().equals("koral:relation")) {
+            if (!relation.has("wrap")) {
+                throw new QueryException(718, "Missing relation term");
+            }
+            SpanQueryWrapper relationWrapper = _termFromJson(
+                    relation.get("wrap"),
+                    direction);
+            return new SpanRelationWrapper(relationWrapper, operand1, operand2);
+        }
+        else {
+            throw new QueryException(713, "Query type is not supported");
+        }
     }
 
 
diff --git a/src/main/java/de/ids_mannheim/korap/query/SimpleSpanQuery.java b/src/main/java/de/ids_mannheim/korap/query/SimpleSpanQuery.java
index ff47287..de1e4c8 100644
--- a/src/main/java/de/ids_mannheim/korap/query/SimpleSpanQuery.java
+++ b/src/main/java/de/ids_mannheim/korap/query/SimpleSpanQuery.java
@@ -72,9 +72,10 @@
 
     protected SpanQuery firstClause = null, secondClause = null;
     protected List<SpanQuery> clauseList = null;
-    private String field;
+    protected String field;
     protected boolean collectPayloads;
 
+    public SimpleSpanQuery () {}
 
     /**
      * Constructs a new SimpleSpanQuery using the specified
diff --git a/src/main/java/de/ids_mannheim/korap/query/SpanFocusQuery.java b/src/main/java/de/ids_mannheim/korap/query/SpanFocusQuery.java
index 305e42c..c144a58 100644
--- a/src/main/java/de/ids_mannheim/korap/query/SpanFocusQuery.java
+++ b/src/main/java/de/ids_mannheim/korap/query/SpanFocusQuery.java
@@ -21,16 +21,13 @@
  * Modify the span of a match to the boundaries of a certain class.
  * 
  * In case multiple classes are found with the very same number, the
- * span is
- * maximized to start on the first occurrence from the left and end on
- * the last
- * occurrence on the right.
+ * span is maximized to start on the first occurrence from the left
+ * and end on the last occurrence on the right.
  * 
  * In case the class to modify on is not found in the subquery, the
- * match is
- * ignored.
+ * match is ignored.
  * 
- * @author diewald
+ * @author diewald, margaretha
  * 
  * @see FocusSpans
  */
@@ -38,7 +35,8 @@
 
     private List<Byte> classNumbers = new ArrayList<Byte>();
     private boolean isSorted = true;
-
+    private boolean matchTemporaryClass = false;
+    private boolean removeTemporaryClasses = false;
 
     /**
      * Construct a new SpanFocusQuery.
@@ -59,7 +57,6 @@
     public SpanFocusQuery (SpanQuery sq, List<Byte> classNumbers) {
         super(sq, true);
         this.classNumbers = classNumbers;
-        isSorted = false;
     };
 
 
@@ -83,6 +80,9 @@
     public String toString (String field) {
         StringBuffer buffer = new StringBuffer();
         buffer.append("focus(");
+        if (matchTemporaryClass){
+            buffer.append("#");
+        }
         if (classNumbers.size() > 1) {
             buffer.append("[");
             for (int i = 0; i < classNumbers.size(); i++) {
@@ -133,6 +133,9 @@
         SpanFocusQuery spanFocusQuery = new SpanFocusQuery(
                 (SpanQuery) this.firstClause.clone(), this.getClassNumbers());
         spanFocusQuery.setBoost(getBoost());
+        spanFocusQuery.setMatchTemporaryClass(this.matchTemporaryClass);
+        spanFocusQuery.setSorted(this.isSorted);
+        spanFocusQuery.setRemoveTemporaryClasses(this.removeTemporaryClasses);
         return spanFocusQuery;
     };
 
@@ -185,4 +188,20 @@
         this.isSorted = isSorted;
     }
 
+    public boolean matchTemporaryClass() {
+        return matchTemporaryClass;
+    }
+
+    public void setMatchTemporaryClass(boolean matchTemporaryClass) {
+        this.matchTemporaryClass = matchTemporaryClass;
+    }
+
+    public boolean removeTemporaryClasses() {
+        return removeTemporaryClasses;
+    }
+
+    public void setRemoveTemporaryClasses(boolean rem) {
+        this.removeTemporaryClasses = rem;
+    }
+
 };
diff --git a/src/main/java/de/ids_mannheim/korap/query/SpanRelationMatchQuery.java b/src/main/java/de/ids_mannheim/korap/query/SpanRelationMatchQuery.java
new file mode 100644
index 0000000..5bc962a
--- /dev/null
+++ b/src/main/java/de/ids_mannheim/korap/query/SpanRelationMatchQuery.java
@@ -0,0 +1,125 @@
+package de.ids_mannheim.korap.query;
+
+import java.io.IOException;
+import java.util.Map;
+
+import org.apache.lucene.index.AtomicReaderContext;
+import org.apache.lucene.index.Term;
+import org.apache.lucene.index.TermContext;
+import org.apache.lucene.search.spans.SpanQuery;
+import org.apache.lucene.search.spans.Spans;
+import org.apache.lucene.util.Bits;
+
+import de.ids_mannheim.korap.query.spans.FocusSpans;
+
+public class SpanRelationMatchQuery extends SimpleSpanQuery{
+
+    private SpanQuery operandQuery;
+    private SpanQuery operand2Query;
+    private SpanRelationQuery relationQuery;
+
+    public SpanRelationMatchQuery (SpanRelationQuery relation, SpanQuery operand,
+            boolean collectPayloads) {
+
+        checkVariables(relation, operand);
+        SpanFocusQuery sq = new SpanFocusQuery(new SpanSegmentQuery(
+                relationQuery, operandQuery, true),
+                relation.getTempClassNumbers());
+        sq.setMatchTemporaryClass(true);
+        sq.setRemoveTemporaryClasses(true);
+        sq.setSorted(false); // which operand to focus might be
+                             // different from that to match
+
+        this.setFirstClause(sq);
+        this.collectPayloads = collectPayloads;
+    }
+
+    public SpanRelationMatchQuery (SpanRelationQuery relation, SpanQuery source,
+            SpanQuery target, boolean collectPayloads) {
+
+        checkVariables(relation, source, target);
+        SpanFocusQuery sq = null;
+        // match source
+        if (relationQuery.getDirection() == 0) {
+            sq = new SpanFocusQuery(new SpanSegmentQuery(relationQuery,
+                    operandQuery, true), relation.getTempTargetNum());
+        }
+        // match target
+        else {
+            sq = new SpanFocusQuery(new SpanSegmentQuery(relationQuery,
+                    operandQuery, true), relation.getTempSourceNum());
+        }
+        sq.setSorted(false);
+        sq.setMatchTemporaryClass(true);
+
+        SpanFocusQuery sq2 = new SpanFocusQuery(new SpanSegmentQuery(sq,
+                operand2Query, true), relation.getTempClassNumbers());
+        sq2.setMatchTemporaryClass(true);
+        sq2.setRemoveTemporaryClasses(true);
+        sq2.setSorted(false);
+
+        this.setFirstClause(sq2);
+        this.collectPayloads = collectPayloads;
+
+    }
+
+    public void checkVariables(SpanRelationQuery relation, SpanQuery operand) {
+        if (relation == null) {
+            throw new IllegalArgumentException(
+                    "The relation query cannot be null.");
+        }
+        if (operand == null) {
+            throw new IllegalArgumentException(
+                    "The operand query cannot be null.");
+        }
+        this.field = relation.getField();
+        if (!operand.getField().equals(field)) {
+            throw new IllegalArgumentException(
+                    "Clauses must have the same field.");
+        }
+        this.relationQuery = relation;
+        this.operandQuery = operand;
+    }
+    
+    public void checkVariables(SpanRelationQuery relation, SpanQuery operand, SpanQuery target) {
+        checkVariables(relation, operand);
+        if (target == null) {
+            if (operand == null) {
+                throw new IllegalArgumentException(
+                        "The target query cannot be null.");
+            }
+        }
+        if (!target.getField().equals(field)) {
+            throw new IllegalArgumentException(
+                    "Clauses must have the same field.");
+        }
+        this.operand2Query = target;
+    }
+
+    @Override
+    public SimpleSpanQuery clone() {
+        if (operand2Query != null) {
+            return new SpanRelationMatchQuery(
+                    (SpanRelationQuery) relationQuery.clone(),
+                    (SpanQuery) operandQuery.clone(),
+                    (SpanQuery) operand2Query.clone(), collectPayloads);
+        }
+
+        return new SpanRelationMatchQuery(
+                (SpanRelationQuery) relationQuery.clone(),
+                (SpanQuery) operandQuery.clone(), collectPayloads);
+    }
+
+    @Override
+    public Spans getSpans(AtomicReaderContext context, Bits acceptDocs,
+            Map<Term, TermContext> termContexts) throws IOException {
+
+        return new FocusSpans((SpanFocusQuery) firstClause, context,
+                acceptDocs, termContexts);
+    }
+
+    @Override
+    public String toString(String field) {
+        return getFirstClause().toString();
+    }
+}
diff --git a/src/main/java/de/ids_mannheim/korap/query/SpanRelationQuery.java b/src/main/java/de/ids_mannheim/korap/query/SpanRelationQuery.java
index 8df29b3..8d06a7e 100644
--- a/src/main/java/de/ids_mannheim/korap/query/SpanRelationQuery.java
+++ b/src/main/java/de/ids_mannheim/korap/query/SpanRelationQuery.java
@@ -1,6 +1,8 @@
 package de.ids_mannheim.korap.query;
 
 import java.io.IOException;
+import java.util.Arrays;
+import java.util.List;
 import java.util.Map;
 
 import org.apache.lucene.index.AtomicReaderContext;
@@ -55,7 +57,12 @@
 public class SpanRelationQuery extends SimpleSpanQuery {
 
     private int direction = 0;
+    private byte tempSourceNum = 1;
+    private byte tempTargetNum = 2;
+    private byte sourceClass;
+    private byte targetClass;
 
+    private List<Byte> tempClassNumbers = Arrays.asList(tempSourceNum, tempTargetNum);
     /**
      * Constructs a SpanRelationQuery based on the given span query.
      * 
@@ -76,6 +83,13 @@
         }
     }
 
+    public SpanRelationQuery (SpanQuery firstClause, List<Byte> classNumbers,
+            boolean collectPayloads) {
+        this(firstClause, collectPayloads);
+        this.tempClassNumbers = classNumbers;
+        this.tempSourceNum = classNumbers.get(0);
+        this.tempTargetNum = classNumbers.get(1);
+    }
 
     @Override
     public SimpleSpanQuery clone () {
@@ -95,9 +109,25 @@
     @Override
     public String toString (String field) {
         StringBuilder sb = new StringBuilder();
+        if (sourceClass > 0) {
+            sb.append("{");
+            sb.append(sourceClass);
+            sb.append(": source:");
+        }
+        if (targetClass > 0) {
+            sb.append("{");
+            sb.append(targetClass);
+            sb.append(": target:");
+        }
         sb.append("spanRelation(");
         sb.append(firstClause.toString(field));
         sb.append(")");
+        if (sourceClass > 0) {
+            sb.append("}");
+        }
+        if (targetClass > 0) {
+            sb.append("}");
+        }
         sb.append(ToStringUtils.boost(getBoost()));
         return sb.toString();
     }
@@ -110,4 +140,54 @@
         this.direction = direction;
     }
 
+    public List<Byte> getTempClassNumbers() {
+        return tempClassNumbers;
+    }
+
+    public void setTempClassNumbers(List<Byte> classNumbers) {
+        this.tempClassNumbers = classNumbers;
+    }
+
+    public byte getTempSourceNum() {
+        return tempSourceNum;
+    }
+
+    public void setTempSourceNum(byte sourceNum) {
+        this.tempSourceNum = sourceNum;
+    }
+
+    public byte getTempTargetNum() {
+        return tempTargetNum;
+    }
+
+    public void setTempTargetNum(byte targetNum) {
+        this.tempTargetNum = targetNum;
+    }
+
+    public byte getSourceClass() {
+        return sourceClass;
+    }
+
+    public void setSourceClass(byte sourceClass)
+            throws IllegalArgumentException {
+        if (sourceClass < 1) {
+            throw new IllegalArgumentException(
+                    "Class number must be bigger than 0.");
+        }
+
+        this.sourceClass = sourceClass;
+    }
+
+    public byte getTargetClass() {
+        return targetClass;
+    }
+
+    public void setTargetClass(byte targetClass)
+            throws IllegalArgumentException {
+        if (targetClass < 1) {
+            throw new IllegalArgumentException(
+                    "Class number must be bigger than 0.");
+        }
+        this.targetClass = targetClass;
+    }
 }
diff --git a/src/main/java/de/ids_mannheim/korap/query/SpanSegmentQuery.java b/src/main/java/de/ids_mannheim/korap/query/SpanSegmentQuery.java
index bb69d4c..7e75543 100644
--- a/src/main/java/de/ids_mannheim/korap/query/SpanSegmentQuery.java
+++ b/src/main/java/de/ids_mannheim/korap/query/SpanSegmentQuery.java
@@ -46,7 +46,6 @@
         this(firstClause, secondClause, true);
     }
 
-
     /**
      * Constructs a SpanSegmentQuery from the two given SpanQueries.
      * 
@@ -61,16 +60,11 @@
      *            <code>false</code>.
      */
     public SpanSegmentQuery (SpanQuery firstClause, SpanQuery secondClause,
-                             boolean collectPayloads) {
+            boolean collectPayloads) {
         super(firstClause, secondClause, collectPayloads);
-    }
-
-
-    public SpanSegmentQuery (SpanRelationQuery firstClause,
-                             SimpleSpanQuery secondClause,
-                             boolean collectPayloads) {
-        super(firstClause, secondClause, true);
-        isRelation = true;
+        if (firstClause instanceof SpanRelationQuery) {
+            isRelation = true;
+        }
     }
 
 
diff --git a/src/main/java/de/ids_mannheim/korap/query/spans/ClassSpans.java b/src/main/java/de/ids_mannheim/korap/query/spans/ClassSpans.java
index 4e97dbc..ac83c4d 100644
--- a/src/main/java/de/ids_mannheim/korap/query/spans/ClassSpans.java
+++ b/src/main/java/de/ids_mannheim/korap/query/spans/ClassSpans.java
@@ -26,16 +26,16 @@
  * @author diewald
  */
 
-public class ClassSpans extends Spans {
-    private List<byte[]> classedPayload;
-    private final Spans spans;
-    private byte number;
-    private SpanQuery operand;
-    private Boolean hasmorespans = false;
+public class ClassSpans extends SimpleSpans {
+    protected List<byte[]> classedPayload;
+    protected Spans spans;
+    protected byte number;
+    protected SpanQuery operand;
+    protected Boolean hasmorespans = false;
 
-    private ByteBuffer bb = ByteBuffer.allocate(9);
+    protected ByteBuffer bb;
 
-    private final static Logger log = LoggerFactory.getLogger(ClassSpans.class);
+    private final Logger log = LoggerFactory.getLogger(ClassSpans.class);
 
     // This advices the java compiler to ignore all loggings
     public static final boolean DEBUG = false;
@@ -69,6 +69,8 @@
 
         // The highlighted payload
         this.classedPayload = new ArrayList<byte[]>(3);
+
+        this.bb = ByteBuffer.allocate(9);
     };
 
 
@@ -126,7 +128,7 @@
     };
 
 
-    private boolean addClassPayload () throws IOException {
+    protected boolean addClassPayload() throws IOException {
         hasmorespans = true;
 
         classedPayload.clear();
@@ -149,6 +151,12 @@
 
         // Add highlight information as byte array
         classedPayload.add(bb.array());
+        
+        if (spans instanceof SimpleSpans) {
+            SimpleSpans ss = (SimpleSpans) spans;
+            this.hasSpanId = ss.hasSpanId;
+            this.spanId = ss.spanId;
+        }
         return true;
     };
 
diff --git a/src/main/java/de/ids_mannheim/korap/query/spans/FocusSpans.java b/src/main/java/de/ids_mannheim/korap/query/spans/FocusSpans.java
index 2da1558..ae3fe59 100644
--- a/src/main/java/de/ids_mannheim/korap/query/spans/FocusSpans.java
+++ b/src/main/java/de/ids_mannheim/korap/query/spans/FocusSpans.java
@@ -52,12 +52,10 @@
     // This advices the java compiler to ignore all loggings
     public static final boolean DEBUG = false;
 
-    // private SimpleSpans originalSpans;
-    private boolean isSorted;
+    private boolean isSorted, matchTemporaryClass, removeTemporaryClasses;
     private List<CandidateSpan> candidateSpans;
     private int windowSize = 10;
     private int currentDoc;
-    private byte number;
 
 
     /**
@@ -86,13 +84,16 @@
         }
         classNumbers = query.getClassNumbers();
         isSorted = query.isSorted();
+        matchTemporaryClass = query.matchTemporaryClass();
+        removeTemporaryClasses = query.removeTemporaryClasses();
         candidateSpans = new ArrayList<CandidateSpan>();
         hasMoreSpans = firstSpans.next();
         currentDoc = firstSpans.doc();
 
-        // matchPayload = new ArrayList<byte[]>(6);
         this.query = query;
-        hasSpanId = true;
+        if (getSpanId() > 0) {
+            hasSpanId = true;
+        }
     }
 
 
@@ -164,7 +165,8 @@
         for (byte[] payload : firstSpans.getPayload()) {
             // No class payload - ignore
             // this may be problematic for other calculated payloads!
-            if (payload.length == 9) {
+            if ((!matchTemporaryClass && payload.length == 9)
+                    || (matchTemporaryClass && payload.length == 10)) {
                 if (classNumbers.contains(payload[8])) {
                     isClassFound = true;
                     classStart = byte2int(payload, 0);
@@ -178,9 +180,12 @@
                         maxPos = classEnd;
                     }
                 }
-                candidateSpan.getPayloads().add(payload.clone());
             }
 
+            if (removeTemporaryClasses && payload.length == 10) {
+                continue;
+            }
+            candidateSpan.getPayloads().add(payload.clone());
         }
 
         if (isClassFound) {
diff --git a/src/main/java/de/ids_mannheim/korap/query/spans/RelationSpans.java b/src/main/java/de/ids_mannheim/korap/query/spans/RelationSpans.java
index f17043d..66afdbe 100644
--- a/src/main/java/de/ids_mannheim/korap/query/spans/RelationSpans.java
+++ b/src/main/java/de/ids_mannheim/korap/query/spans/RelationSpans.java
@@ -58,7 +58,8 @@
 
     protected Logger logger = LoggerFactory.getLogger(RelationSpans.class);
     private List<CandidateRelationSpan> candidateList;
-
+    private byte tempSourceNum, tempTargetNum;
+    private byte sourceClass, targetClass;
 
     /**
      * Constructs RelationSpans from the given
@@ -77,6 +78,11 @@
             throws IOException {
         super(relationSpanQuery, context, acceptDocs, termContexts);
         direction = relationSpanQuery.getDirection();
+        tempSourceNum = relationSpanQuery.getTempSourceNum();
+        tempTargetNum = relationSpanQuery.getTempTargetNum();
+        sourceClass = relationSpanQuery.getSourceClass();
+        targetClass = relationSpanQuery.getTargetClass();
+
         candidateList = new ArrayList<>();
         relationTermSpan = (TermSpans) firstSpans;
         hasMoreSpans = relationTermSpan.next();
@@ -213,22 +219,47 @@
         }
         if (direction == 0) {
             payload.add(createClassPayload(cs.getLeftStart(), cs.getLeftEnd(),
-                    (byte) 1));
+                    tempSourceNum, false));
             payload.add(createClassPayload(cs.getRightStart(),
-                    cs.getRightEnd(), (byte) 2));
+                    cs.getRightEnd(), tempTargetNum, false));
+
+            if (sourceClass > 0) {
+                payload.add(createClassPayload(cs.getLeftStart(),
+                        cs.getLeftEnd(), sourceClass, true));
+            }
+            if (targetClass > 0) {
+                payload.add(createClassPayload(cs.getRightStart(),
+                        cs.getRightEnd(), targetClass, true));
+            }
+
         }
         else {
             payload.add(createClassPayload(cs.getRightStart(),
-                    cs.getRightEnd(), (byte) 1));
+                    cs.getRightEnd(), tempSourceNum, false));
             payload.add(createClassPayload(cs.getLeftStart(), cs.getLeftEnd(),
-                    (byte) 2));
+                    tempTargetNum, false));
+
+            if (sourceClass > 0) {
+                payload.add(createClassPayload(cs.getRightStart(),
+                        cs.getRightEnd(), sourceClass, true));
+            }
+            if (targetClass > 0) {
+                payload.add(createClassPayload(cs.getLeftStart(),
+                        cs.getLeftEnd(), targetClass, true));
+            }
         }
         cs.setPayloads(payload);
     }
 
-
-    private byte[] createClassPayload (int start, int end, byte classNumber) {
-        ByteBuffer buffer = ByteBuffer.allocate(9);
+    private byte[] createClassPayload(int start, int end, byte classNumber,
+            boolean keep) {
+        ByteBuffer buffer = null;
+        if (keep) {
+            buffer = ByteBuffer.allocate(9);
+        }
+        else {
+            buffer = ByteBuffer.allocate(10);
+        }
         buffer.putInt(start);
         buffer.putInt(end);
         buffer.put(classNumber);
diff --git a/src/main/java/de/ids_mannheim/korap/query/spans/SegmentSpans.java b/src/main/java/de/ids_mannheim/korap/query/spans/SegmentSpans.java
index 8ac53b8..9d40d31 100644
--- a/src/main/java/de/ids_mannheim/korap/query/spans/SegmentSpans.java
+++ b/src/main/java/de/ids_mannheim/korap/query/spans/SegmentSpans.java
@@ -94,6 +94,7 @@
     protected int findMatch () {
         RelationSpans s1;
         SimpleSpans s2;
+
         if (firstSpans.start() == secondSpans.start()
                 && firstSpans.end() == secondSpans.end()) {
 
@@ -101,13 +102,18 @@
                 s1 = (RelationSpans) firstSpans;
                 s2 = (SimpleSpans) secondSpans;
 
-                //System.out.println("segment: " + s1.getRightStart() + " "
-                // + s1.getRightEnd());
-                if (s1.getLeftId() == s2.getSpanId()) {
+                if (s2.hasSpanId) {
+                    if (s1.getLeftId() == s2.getSpanId()) {
+                        setSpanId(s2.getSpanId());
+                        setMatch();
+                        return 0;
+                    }
+                }
+                else {
                     setMatch();
-                    setSpanId(s2.getSpanId());
                     return 0;
                 }
+
             }
             else {
                 setMatch();
diff --git a/src/main/java/de/ids_mannheim/korap/query/wrap/SpanRelationWrapper.java b/src/main/java/de/ids_mannheim/korap/query/wrap/SpanRelationWrapper.java
index 17afa22..2535ce9 100644
--- a/src/main/java/de/ids_mannheim/korap/query/wrap/SpanRelationWrapper.java
+++ b/src/main/java/de/ids_mannheim/korap/query/wrap/SpanRelationWrapper.java
@@ -1,11 +1,11 @@
 package de.ids_mannheim.korap.query.wrap;
 
-import java.util.ArrayList;
-
 import org.apache.lucene.search.spans.SpanQuery;
+import org.apache.lucene.search.spans.SpanTermQuery;
 
 import de.ids_mannheim.korap.query.SpanFocusQuery;
-import de.ids_mannheim.korap.query.SpanSegmentQuery;
+import de.ids_mannheim.korap.query.SpanRelationMatchQuery;
+import de.ids_mannheim.korap.query.SpanRelationQuery;
 import de.ids_mannheim.korap.util.QueryException;
 
 public class SpanRelationWrapper extends SpanQueryWrapper {
@@ -13,12 +13,9 @@
     private SpanQueryWrapper relationQuery;
     private SpanQueryWrapper subQuery1;
     private SpanQueryWrapper subQuery2;
-    private byte[] classNumbers;
-
 
     public SpanRelationWrapper (SpanQueryWrapper relationWrapper,
-                                SpanQueryWrapper operand1,
-                                SpanQueryWrapper operand2, byte[] classNumbers) {
+            SpanQueryWrapper operand1, SpanQueryWrapper operand2) {
 
         this.relationQuery = relationWrapper;
         if (relationQuery != null) {
@@ -34,70 +31,63 @@
 
         this.subQuery1 = operand1;
         this.subQuery2 = operand2;
-        this.classNumbers = classNumbers;
     }
 
 
     @Override
-    public SpanQuery toQuery () throws QueryException {
+    public SpanQuery toQuery() throws QueryException {
 
         if (this.isNull() || this.isEmpty()) {
             return null;
         }
 
-        SpanQuery sq = relationQuery.retrieveNode(this.retrieveNode).toQuery();
-        if (sq == null)
+        SpanTermQuery relationTermQuery = (SpanTermQuery) relationQuery.retrieveNode(
+                this.retrieveNode).toQuery();
+        if (relationTermQuery == null)
             return null;
-
+        
+        SpanRelationQuery rq = new SpanRelationQuery(relationTermQuery, true);
         SpanQuery subq1, subq2;
+
         if (subQuery1.isEmpty) {
             if (!subQuery2.isEmpty) {
                 // match target
                 subq2 = subQuery2.retrieveNode(this.retrieveNode).toQuery();
-                if (subq2 != null) {
-                    return createQuery(new SpanSegmentQuery(sq, subq2, true));
+                if (subQuery1.hasClass) {
+                    rq.setSourceClass(subQuery1.getClassNumber());
                 }
+
+                return new SpanRelationMatchQuery(rq, subq2, true);
             }
         }
         else if (subQuery2.isEmpty) {
             if (!subQuery1.isEmpty) {
                 // match source
                 subq1 = subQuery1.retrieveNode(this.retrieveNode).toQuery();
-                if (subq1 != null) {
-                    return createQuery(new SpanSegmentQuery(sq, subq1, true));
+                if (subQuery2.hasClass) {
+                    rq.setTargetClass(subQuery2.getClassNumber());
                 }
+                return new SpanRelationMatchQuery(rq, subq1, true);
             }
         }
         else {
             // match both
             subq1 = subQuery1.retrieveNode(this.retrieveNode).toQuery();
-            if (subq1 != null) {
-                SpanFocusQuery fq = new SpanFocusQuery(new SpanSegmentQuery(sq,
-                        subq1, true), (byte) 2);
-                fq.setSorted(false);
-                sq = fq;
-            }
-
             subq2 = subQuery2.retrieveNode(this.retrieveNode).toQuery();
-            if (subq2 != null) {
-                return createQuery(new SpanSegmentQuery(sq, subq2, true));
-            }
+            return new SpanRelationMatchQuery(rq, subq1, subq2, true);
         }
 
-        return createQuery(sq);
-    }
-
-    private SpanQuery createQuery(SpanQuery sq) {
-        ArrayList<Byte> classNumbers = new ArrayList<Byte>();
-        if (this.classNumbers != null) {
-            for (byte c : this.classNumbers) {
-                if (c > 0) {
-                    classNumbers.add(c);
-                }
-            }
-            return new SpanFocusQuery(sq, classNumbers);
+        // both empty
+        if (subQuery1.hasClass) {
+            rq.setSourceClass(subQuery1.getClassNumber());
         }
-        return sq;
-
+        if (subQuery2.hasClass) {
+            rq.setTargetClass(subQuery2.getClassNumber());
+        }
+        SpanFocusQuery fq = new SpanFocusQuery(rq, rq.getTempClassNumbers());
+        fq.setMatchTemporaryClass(true);
+        fq.setRemoveTemporaryClasses(true);
+        fq.setSorted(false);
+        return fq;
     }
 }
diff --git a/src/test/java/de/ids_mannheim/korap/index/TestRelationIndex.java b/src/test/java/de/ids_mannheim/korap/index/TestRelationIndex.java
index e0d6598..a183fe8 100644
--- a/src/test/java/de/ids_mannheim/korap/index/TestRelationIndex.java
+++ b/src/test/java/de/ids_mannheim/korap/index/TestRelationIndex.java
@@ -3,7 +3,6 @@
 import static org.junit.Assert.assertEquals;
 
 import java.io.IOException;
-import java.util.ArrayList;
 
 import org.apache.lucene.index.Term;
 import org.apache.lucene.search.spans.SpanQuery;
@@ -12,8 +11,10 @@
 
 import de.ids_mannheim.korap.KrillIndex;
 import de.ids_mannheim.korap.query.SpanAttributeQuery;
+import de.ids_mannheim.korap.query.SpanClassQuery;
 import de.ids_mannheim.korap.query.SpanElementQuery;
 import de.ids_mannheim.korap.query.SpanFocusQuery;
+import de.ids_mannheim.korap.query.SpanRelationMatchQuery;
 import de.ids_mannheim.korap.query.SpanRelationQuery;
 import de.ids_mannheim.korap.query.SpanSegmentQuery;
 import de.ids_mannheim.korap.query.SpanTermWithIdQuery;
@@ -128,7 +129,7 @@
                         + "<:child-of$<i>0<s>3<s>3<s>1|"
                         + "<:child-of$<i>7<i>0<i>1<s>4<s>2<s>3|"
                         + "<:child-of$<i>7<i>1<i>7<s>5<s>2<s>2|"
-                        + "<:dep$<i>1<s>2<s>1<s>1|"
+                        + "<:dep$<i>0<s>2<s>1<s>1|"
                         + "r@:func=sbj$<i>0<i>7<s>1]"
                         +
 
@@ -149,14 +150,15 @@
                         + "<:child-of$<i>4<b>0<i>3<s>14<s>3<s>1|"
                         + "<:child-of$<i>7<i>2<i>4<s>15<s>4<s>3|"
                         + "<:child-of$<i>7<i>4<i>7<s>16<s>4<s>2|"
-                        + "<:dep$<i>3<s>2<s>1<s>1]" +
+                        + ">:parent-of$<i>7<i>4<i>7<s>17<s>4<s>2|"
+                        + "<:dep$<i>3<s>3<s>1<s>1]" +
 
                         "[(3-4)s:Blümen|_3#14-20|pos:NN$<s>1|"
                         + ">:child-of$<i>2<i>4<s>17<s>1<s>3|"
                         + "<:dep$<i>1<s>2<s>1<s>1|" + ">:dep$<i>2<s>3<s>1<s>1|"
                         + ">:dep$<i>4<s>4<s>1<s>1|"
-                        + "r@:func=head$<i>2<i>4<s>2|"
-                        + "r@:func=obj$<i>1<i>4<s>2]" +
+                        + "r@:func=head$<i>2<i>4<s>3|"
+                        + "r@:func=obj$<i>2<i>4<s>3]" +
 
                         "[(4-5)s:für|_4#21-24|pos:PREP$<s>1|<>:pp#21-38$<i>7<s>2|"
                         + ">:child-of$<i>4<i>7<s>18<s>1<s>2|"
@@ -261,9 +263,7 @@
 
 
     /**
-     * Relations with attributes
-     * need focusMulti on span relation query before
-     * SpanWithAttributeQuery
+     * Relations only
      * */
     @Test
     public void testCase3 () throws IOException {
@@ -288,32 +288,11 @@
         assertEquals(3, kr.getMatch(4).getEndPos());
         assertEquals(2, kr.getMatch(5).getStartPos());
         assertEquals(4, kr.getMatch(5).getEndPos());
-
-        ArrayList<Byte> classNumbers = new ArrayList<Byte>();
-        classNumbers.add((byte) 1);
-        classNumbers.add((byte) 2);
-
-        SpanFocusQuery fq = new SpanFocusQuery(srq, classNumbers);
-        kr = ki.search(fq, (short) 20);
-        /*
-         * for (Match km : kr.getMatches()) {
-         * System.out.println(km.getStartPos() + "," + km.getEndPos()
-         * + " " + km.getSnippetBrackets()); }
-         */
-        assertEquals((long) 13, kr.getTotalResults());
-        assertEquals(0, kr.getMatch(0).getStartPos());
-        assertEquals(1, kr.getMatch(0).getEndPos());
-        assertEquals(0, kr.getMatch(1).getStartPos());
-        assertEquals(7, kr.getMatch(1).getEndPos());
-        assertEquals(0, kr.getMatch(2).getStartPos());
-        assertEquals(7, kr.getMatch(2).getEndPos());
-        assertEquals(1, kr.getMatch(3).getStartPos());
-        assertEquals(7, kr.getMatch(3).getEndPos());
-        assertEquals(1, kr.getMatch(4).getStartPos());
-        assertEquals(7, kr.getMatch(4).getEndPos());
     }
 
-
+    /**
+     * Relations only with/out attribute
+     * */
     @Test
     public void testCase4 () throws IOException {
         ki.addDoc(createFieldDoc2());
@@ -322,12 +301,14 @@
         SpanRelationQuery srq = new SpanRelationQuery(new SpanTermQuery(
                 new Term("base", ">:child-of")), true);
 
-        ArrayList<Byte> classNumbers = new ArrayList<Byte>();
-        classNumbers.add((byte) 1);
-        classNumbers.add((byte) 2);
+        SpanFocusQuery fq = new SpanFocusQuery(srq, srq.getTempClassNumbers());
+        fq.setMatchTemporaryClass(true);
+        fq.setRemoveTemporaryClasses(true);
+        fq.setSorted(false);
 
-        SpanWithAttributeQuery wq = new SpanWithAttributeQuery(
-                new SpanFocusQuery(srq, classNumbers), new SpanAttributeQuery(
+        // child-of with attr func=sbj
+        SpanWithAttributeQuery wq = new SpanWithAttributeQuery(fq,
+                new SpanAttributeQuery(
                         new SpanTermQuery(new Term("base", "r@:func=sbj")),
                         true), true);
 
@@ -337,7 +318,7 @@
         assertEquals(7, kr.getMatch(0).getEndPos());
 
         // child-of without attr func=sbj
-        wq = new SpanWithAttributeQuery(new SpanFocusQuery(srq, classNumbers),
+        wq = new SpanWithAttributeQuery(fq,
                 new SpanAttributeQuery(new SpanTermQuery(new Term("base",
                         "r@:func=sbj")), true, true), true);
         kr = ki.search(wq, (short) 20);
@@ -345,87 +326,9 @@
     }
 
 
-    @Test
-    public void testCase5 () throws IOException {
-
-        ki.addDoc(createFieldDoc2());
-        ki.commit();
-
-        SpanRelationQuery srq = new SpanRelationQuery(new SpanTermQuery(
-                new Term("base", "<:dep")), true);
-        kr = ki.search(srq, (short) 10);
-
-        ArrayList<Byte> classNumbers = new ArrayList<Byte>();
-        classNumbers.add((byte) 1);
-        classNumbers.add((byte) 2);
-
-        SpanFocusQuery fq = new SpanFocusQuery(srq, classNumbers);
-        kr = ki.search(fq, (short) 10);
-        // for (Match km : kr.getMatches()) {
-        // System.out.println(km.getStartPos() + "," + km.getEndPos()
-        // + " "
-        // + km.getSnippetBrackets());
-        // }
-
-        SpanAttributeQuery saq = new SpanAttributeQuery(new SpanTermQuery(
-                new Term("base", "r@:func=obj")), true);
-        kr = ki.search(saq, (short) 10);
-
-        // child-of with attr func-obj
-        SpanWithAttributeQuery wq = new SpanWithAttributeQuery(
-                new SpanFocusQuery(srq, classNumbers), new SpanAttributeQuery(
-                        new SpanTermQuery(new Term("base", "r@:func=obj")),
-                        true), true);
-
-        kr = ki.search(wq, (short) 10);
-        assertEquals((long) 1, kr.getTotalResults());
-        assertEquals(1, kr.getMatch(0).getStartPos()); // element
-        assertEquals(4, kr.getMatch(0).getEndPos());
-    }
-
-
-    @Test
-    public void testCase10 () throws IOException {
-        ki.addDoc(createFieldDoc2());
-        ki.commit();
-        // target of a dependency relation
-        SpanRelationQuery srq = new SpanRelationQuery(new SpanTermQuery(
-                new Term("base", "<:dep")), true);
-        kr = ki.search(srq, (short) 10);
-        assertEquals((long) 6, kr.getTotalResults());
-
-        ArrayList<Byte> classNumbers = new ArrayList<Byte>();
-        classNumbers.add((byte) 1);
-        classNumbers.add((byte) 2);
-
-        SpanFocusQuery fq = new SpanFocusQuery(srq, classNumbers);
-        kr = ki.search(fq, (short) 10);
-        assertEquals((long) 6, kr.getTotalResults());
-
-        SpanAttributeQuery aq = new SpanAttributeQuery(new SpanTermQuery(
-                new Term("base", "r@:func=head")), true);
-        kr = ki.search(aq, (short) 10);
-
-        // dependency relation, which is also a head
-        SpanWithAttributeQuery wq = new SpanWithAttributeQuery(
-                new SpanFocusQuery(srq, classNumbers), new SpanAttributeQuery(
-                        new SpanTermQuery(new Term("base", "r@:func=head")),
-                        true), true);
-
-        kr = ki.search(wq, (short) 20);
-
-        assertEquals((long) 2, kr.getTotalResults());
-        assertEquals(2, kr.getMatch(0).getStartPos());
-        assertEquals(4, kr.getMatch(0).getEndPos());
-        assertEquals(5, kr.getMatch(1).getStartPos());
-        assertEquals(7, kr.getMatch(1).getEndPos());
-
-    }
-
-
     /**
-     * Match left return left
-     * Match right return right
+     * Relation directions <br/>
+     * Relation with specific sources, return the sources
      * */
     @Test
     public void testCase6 () throws IOException {
@@ -433,9 +336,15 @@
         ki.commit();
 
         // return all children that are NP
-        SpanQuery rv = new SpanSegmentQuery(new SpanRelationQuery(
-                new SpanTermQuery(new Term("base", ">:child-of")), true),
-                new SpanElementQuery("base", "np"), true);
+        SpanElementQuery seq1 = new SpanElementQuery("base", "np");
+        SpanClassQuery scq1 = new SpanClassQuery(seq1, (byte) 1);
+
+        SpanRelationQuery srq = new SpanRelationQuery(new SpanTermQuery(
+                new Term("base", ">:child-of")), true);
+
+        SpanRelationMatchQuery rm = new SpanRelationMatchQuery(srq, scq1, true);
+        SpanFocusQuery rv = new SpanFocusQuery(rm, (byte) 1);
+        rv.setSorted(false);
 
         kr = ki.search(rv, (short) 10);
 
@@ -450,10 +359,10 @@
         assertEquals(7, kr.getMatch(3).getEndPos());
 
         // return all parents that are NP
-        rv = new SpanSegmentQuery(new SpanRelationQuery(new SpanTermQuery(
-                new Term("base", "<:child-of")), true), new SpanElementQuery(
-                "base", "np"), true);
-
+        srq = new SpanRelationQuery(new SpanTermQuery(new Term("base",
+                "<:child-of")), true);
+        rm = new SpanRelationMatchQuery(srq, scq1, true);
+        rv = new SpanFocusQuery(rm, (byte) 1);
         kr = ki.search(rv, (short) 10);
 
         assertEquals(7, kr.getTotalResults());
@@ -473,10 +382,53 @@
         assertEquals(7, kr.getMatch(6).getEndPos());
     }
 
+    /**
+     * Dependency relations with attribute
+     * */
+    @Test
+    public void testCase5() throws IOException {
+        ki.addDoc(createFieldDoc2());
+        ki.commit();
+
+        // target of a dependency relation
+        SpanRelationQuery srq = new SpanRelationQuery(new SpanTermQuery(
+                new Term("base", "<:dep")), true);
+        kr = ki.search(srq, (short) 10);
+        assertEquals((long) 6, kr.getTotalResults());
+
+        SpanFocusQuery fq = new SpanFocusQuery(srq, srq.getTempClassNumbers());
+        fq.setMatchTemporaryClass(true);
+        fq.setRemoveTemporaryClasses(true);
+        // fq.setSorted(false);
+
+        kr = ki.search(fq, (short) 10);
+        assertEquals((long) 6, kr.getTotalResults());
+        // for (Match km : kr.getMatches()) {
+        // System.out.println(km.getStartPos() + "," + km.getEndPos()
+        // + " "
+        // + km.getSnippetBrackets());
+        // }
+        SpanAttributeQuery aq = new SpanAttributeQuery(new SpanTermQuery(
+                new Term("base", "r@:func=head")), true);
+        kr = ki.search(aq, (short) 10);
+
+        // dependency relation, which is also a head
+        SpanWithAttributeQuery wq = new SpanWithAttributeQuery(fq,
+                new SpanAttributeQuery(new SpanTermQuery(new Term("base",
+                        "r@:func=head")), true), true);
+
+        kr = ki.search(wq, (short) 20);
+
+        assertEquals((long) 2, kr.getTotalResults());
+        assertEquals(2, kr.getMatch(0).getStartPos());
+        assertEquals(4, kr.getMatch(0).getEndPos());
+        assertEquals(5, kr.getMatch(1).getStartPos());
+        assertEquals(7, kr.getMatch(1).getEndPos());
+
+    }
 
     /**
-     * Match left, return right
-     * sort by left, then sort by right
+     * Relation with specific targets, return any sources
      * */
     @Test
     public void testCase7 () throws IOException {
@@ -484,9 +436,17 @@
         ki.commit();
 
         // return all children that are NP
-        SpanQuery rv = new SpanSegmentQuery(new SpanRelationQuery(
-                new SpanTermQuery(new Term("base", ">:child-of")), true),
-                new SpanElementQuery("base", "np"), true);
+
+        SpanElementQuery seq1 = new SpanElementQuery("base", "np");
+        SpanClassQuery scq1 = new SpanClassQuery(seq1, (byte) 1);
+
+        SpanRelationQuery srq = new SpanRelationQuery(new SpanTermQuery(
+                new Term("base", ">:child-of")), true);
+        srq.setTargetClass((byte) 2);
+
+        SpanRelationMatchQuery rm = new SpanRelationMatchQuery(srq, scq1, true);
+        SpanQuery rv = new SpanFocusQuery(rm, (byte) 1);
+
 
         //return all parents of np
         SpanFocusQuery rv2 = new SpanFocusQuery(rv, (byte) 2);
@@ -519,26 +479,32 @@
         ki.commit();
 
         //return source of dep relations to pos:NN
-        SpanQuery rv = new SpanFocusQuery(new SpanSegmentQuery(
-                new SpanRelationQuery(new SpanTermQuery(new Term("base",
-                        "<:dep")), true), new SpanTermWithIdQuery(new Term(
-                        "base", "pos:NN"), true), true), (byte) 1);
+        
+        SpanTermWithIdQuery tq = new SpanTermWithIdQuery(new Term("base",
+                "pos:NN"), true);
+        SpanRelationQuery srq = new SpanRelationQuery(new SpanTermQuery(new Term("base",
+                "<:dep")), true);
+        srq.setSourceClass((byte) 1);
+        SpanRelationMatchQuery rm = new SpanRelationMatchQuery(srq, tq, true);
+        SpanQuery rv = new SpanFocusQuery(rm, (byte) 1);
 
         kr = ki.search(rv, (short) 10);
         assertEquals((long) 3, kr.getTotalResults());
-        assertEquals(1, kr.getMatch(0).getStartPos());
-        assertEquals(2, kr.getMatch(0).getEndPos());
+        assertEquals(0, kr.getMatch(0).getStartPos());
+        assertEquals(1, kr.getMatch(0).getEndPos());
         assertEquals(1, kr.getMatch(1).getStartPos());
         assertEquals(2, kr.getMatch(1).getEndPos());
         assertEquals(4, kr.getMatch(2).getStartPos());
         assertEquals(5, kr.getMatch(2).getEndPos());
 
-        //return target of dep relations from pos:NN
-        rv = new SpanFocusQuery(
-                new SpanSegmentQuery(new SpanRelationQuery(new SpanTermQuery(
-                        new Term("base", ">:dep")), true),
-                        new SpanTermWithIdQuery(new Term("base", "pos:NN"),
-                                true), true), (byte) 2);
+        // return target of dep relations from pos:NN
+        srq = new SpanRelationQuery(
+                new SpanTermQuery(
+                new Term("base", ">:dep")), true);
+        srq.setTargetClass((byte) 1);
+        rm = new SpanRelationMatchQuery(srq, tq, true);
+        rv = new SpanFocusQuery(rm, (byte) 1);
+
         kr = ki.search(rv, (short) 10);
         assertEquals((long) 3, kr.getTotalResults());
         assertEquals(2, kr.getMatch(0).getStartPos());
@@ -552,8 +518,9 @@
 
 
     /**
-     * Relation with variable match right, return left sort by right,
-     * then sort by left
+     * Relation with specific sources and return any targets <br/>
+     * Relation with specific sources and targets, return the targets <br/>
+     * Relation with specific sources and targets, return the sources
      * 
      * @throws IOException
      * */
@@ -563,10 +530,14 @@
         ki.commit();
 
         // return all children of np
-        SpanFocusQuery rv = new SpanFocusQuery(new SpanSegmentQuery(
-                new SpanRelationQuery(new SpanTermQuery(new Term("base",
-                        "<:child-of")), true), new SpanElementQuery("base",
-                        "np"), true), (byte) 1);
+        SpanElementQuery seq1 = new SpanElementQuery("base", "np");
+        SpanClassQuery scq1 = new SpanClassQuery(seq1, (byte) 1);
+        SpanRelationQuery srq = new SpanRelationQuery(new SpanTermQuery(
+                new Term("base", "<:child-of")), true);
+        srq.setSourceClass((byte) 2);
+        SpanRelationMatchQuery rm = new SpanRelationMatchQuery(srq, scq1, true);
+        SpanFocusQuery rv = new SpanFocusQuery(rm, (byte) 2);
+
         rv.setSorted(false);
 
         kr = ki.search(rv, (short) 10);
@@ -586,12 +557,19 @@
         assertEquals(6, kr.getMatch(5).getEndPos());
         assertEquals(6, kr.getMatch(6).getStartPos());
         assertEquals(7, kr.getMatch(6).getEndPos());
-        // sorting left problem (solved)
 
         // return all children of np that are articles
-        SpanSegmentQuery rv2 = new SpanSegmentQuery(rv, new SpanTermQuery(
-                new Term("base", "pos:ART")));
-        kr = ki.search(rv2, (short) 10);
+
+        SpanTermWithIdQuery tiq = new SpanTermWithIdQuery(new Term("base",
+                "pos:ART"), true);
+        SpanClassQuery scq2 = new SpanClassQuery(tiq, (byte) 2);
+
+        srq = new SpanRelationQuery(new SpanTermQuery(new Term("base",
+                ">:child-of")), true);
+        rm = new SpanRelationMatchQuery(srq, scq2, scq1, true);
+        rv = new SpanFocusQuery(rm, (byte) 2);
+
+        kr = ki.search(rv, (short) 10);
 
         assertEquals((long) 2, kr.getTotalResults());
         assertEquals(2, kr.getMatch(0).getStartPos());
@@ -603,17 +581,41 @@
         SpanSegmentQuery rv3 = new SpanSegmentQuery(rv,
                 new SpanTermWithIdQuery(new Term("base", "pos:ART"), true));
         
-        
         SpanFocusQuery sf = new SpanFocusQuery(rv3, (byte) 1);
         kr = ki.search(sf, (short) 10);
 
         assertEquals((long) 2, kr.getTotalResults());
-
         assertEquals(2, kr.getMatch(0).getStartPos());
-        assertEquals(3, kr.getMatch(0).getEndPos());
+        assertEquals(4, kr.getMatch(0).getEndPos());
         assertEquals(5, kr.getMatch(1).getStartPos());
-        assertEquals(6, kr.getMatch(1).getEndPos());
+        assertEquals(7, kr.getMatch(1).getEndPos());
 
     }
 
+    @Test
+    public void testCase10() throws IOException {
+        ki.addDoc(createFieldDoc2());
+        ki.commit();
+        SpanElementQuery seq1 = new SpanElementQuery("base", "np");
+        SpanElementQuery seq2 = new SpanElementQuery("base", "np");
+        SpanClassQuery scq1 = new SpanClassQuery(seq1, (byte) 1);
+        SpanClassQuery scq2 = new SpanClassQuery(seq2, (byte) 2);
+
+        SpanRelationQuery srq = new SpanRelationQuery(new SpanTermQuery(
+                new Term("base", ">:child-of")), true);
+        SpanRelationMatchQuery rq = new SpanRelationMatchQuery(srq, scq2, true);
+
+        kr = ki.search(rq, (short) 10);
+
+        assertEquals((long) 4, kr.getTotalResults());
+        assertEquals(0, kr.getMatch(0).getStartPos());
+        assertEquals(7, kr.getMatch(0).getEndPos());
+        assertEquals(1, kr.getMatch(1).getStartPos());
+        assertEquals(7, kr.getMatch(1).getEndPos());
+        assertEquals(2, kr.getMatch(2).getStartPos());
+        assertEquals(7, kr.getMatch(2).getEndPos());
+        assertEquals(4, kr.getMatch(3).getStartPos());
+        assertEquals(7, kr.getMatch(3).getEndPos());
+    }
+
 }
\ No newline at end of file
diff --git a/src/test/java/de/ids_mannheim/korap/query/TestSpanRelationQueryJSON.java b/src/test/java/de/ids_mannheim/korap/query/TestSpanRelationQueryJSON.java
index 2512d1d..fccd34a 100644
--- a/src/test/java/de/ids_mannheim/korap/query/TestSpanRelationQueryJSON.java
+++ b/src/test/java/de/ids_mannheim/korap/query/TestSpanRelationQueryJSON.java
@@ -19,7 +19,7 @@
         SpanQueryWrapper sqwi = getJSONQuery(filepath);
         SpanQuery sq = sqwi.toQuery();
         assertEquals(
-                "focus([1,2]spanSegment(tokens:>:mate/d:HEAD, <tokens:c:s />))",
+                "focus(#[1,2]spanSegment(spanRelation(tokens:>:mate/d:HEAD), <tokens:c:s />))",
                 sq.toString());
     }
 
@@ -32,7 +32,7 @@
         SpanQueryWrapper sqwi = getJSONQuery(filepath);
         SpanQuery sq = sqwi.toQuery();
         assertEquals(
-                "focus([1,2]spanSegment(tokens:<:mate/d:HEAD, <tokens:c:vp />))",
+                "focus(#[1,2]spanSegment(spanRelation(tokens:<:mate/d:HEAD), <tokens:c:vp />))",
                 sq.toString());
     }
 
@@ -45,7 +45,7 @@
         SpanQueryWrapper sqwi = getJSONQuery(filepath);
         SpanQuery sq = sqwi.toQuery();
         assertEquals(
-                "focus([1,2]spanSegment(focus(2: spanSegment(tokens:>:mate/d:HEAD, <tokens:c:s />)), <tokens:c:vp />))",
+                "focus(#[1,2]spanSegment(focus(#2: spanSegment(spanRelation(tokens:>:mate/d:HEAD), <tokens:c:s />)), <tokens:c:vp />))",
                 sq.toString());
     }
 
@@ -58,7 +58,7 @@
         SpanQueryWrapper sqwi = getJSONQuery(filepath);
         SpanQuery sq = sqwi.toQuery();
         assertEquals(
-                "focus([1,2]spanSegment(focus(2: spanSegment(tokens:>:mate/d:HEAD, "
+                "focus(#[1,2]spanSegment(focus(#2: spanSegment(spanRelation(tokens:>:mate/d:HEAD), "
                         + "spanElementWithAttribute(<tokens:c:s />, spanAttribute(tokens:@root)))), <tokens:c:vp />))",
                 sq.toString());
     }
@@ -72,7 +72,7 @@
         SpanQueryWrapper sqwi = getJSONQuery(filepath);
         SpanQuery sq = sqwi.toQuery();
         assertEquals(
-                "focus([1,2]spanSegment(focus(2: spanSegment(tokens:>:mate/d:HEAD, "
+                "focus(#[1,2]spanSegment(focus(#2: spanSegment(spanRelation(tokens:>:mate/d:HEAD), "
                         + "spanElementWithAttribute(<tokens:c:s />, spanAttribute(tokens:type:top)))), <tokens:c:vp />))",
                 sq.toString());
     }
@@ -85,7 +85,8 @@
                 "/queries/relation/relation-only.json").getFile();
         SpanQueryWrapper sqwi = getJSONQuery(filepath);
         SpanQuery sq = sqwi.toQuery();
-        assertEquals("focus([1,2]tokens:<:mate/d:HEAD)", sq.toString());
+        assertEquals("focus(#[1,2]spanRelation(tokens:>:mate/d:HEAD))",
+                sq.toString());
     }
 
     @Test
@@ -96,18 +97,41 @@
         SpanQueryWrapper sqwi = getJSONQuery(filepath);
         SpanQuery sq = sqwi.toQuery();
         assertEquals(
-                "focus(1: spanSegment(tokens:<:mate/d:HEAD, <tokens:np />))",
+                "focus(1: focus(#[1,2]spanSegment(spanRelation(tokens:<:mate/d:HEAD), {1: <tokens:c:np />})))",
                 sq.toString());
     }
 
     @Test
-    public void testFocusTarget () throws QueryException {
+    public void testFocusTarget() throws QueryException {
         String filepath = getClass().getResource(
                 "/queries/relation/focus-target.json").getFile();
         SpanQueryWrapper sqwi = getJSONQuery(filepath);
         SpanQuery sq = sqwi.toQuery();
         assertEquals(
-                "focus(2: spanSegment(tokens:>:mate/d:HEAD, <tokens:s />))",
+                "focus(2: focus(#[1,2]spanSegment(focus(#2: spanSegment(spanRelation("
+                        + "tokens:>:mate/d:HEAD), {1: <tokens:c:s />})), {2: <tokens:c:np />})))",
+                sq.toString());
+    }
+
+    @Test
+    public void testFocusEmptyTarget() throws QueryException {
+        String filepath = getClass().getResource(
+                "/queries/relation/focus-empty-target.json").getFile();
+        SpanQueryWrapper sqwi = getJSONQuery(filepath);
+        SpanQuery sq = sqwi.toQuery();
+        assertEquals(
+                "focus(2: focus(#[1,2]spanSegment({2: target:spanRelation(tokens:>:mate/d:HEAD)}, {1: <tokens:c:s />})))",
+                sq.toString());
+    }
+
+    @Test
+    public void testFocusEmptyBoth() throws QueryException {
+        String filepath = getClass().getResource(
+                "/queries/relation/focus-empty-both.json").getFile();
+        SpanQueryWrapper sqwi = getJSONQuery(filepath);
+        SpanQuery sq = sqwi.toQuery();
+        assertEquals(
+                "focus(2: focus(#[1,2]{1: source:{2: target:spanRelation(tokens:>:mate/d:HEAD)}}))",
                 sq.toString());
     }
 }
diff --git a/src/test/java/de/ids_mannheim/korap/search/TestKrill.java b/src/test/java/de/ids_mannheim/korap/search/TestKrill.java
index 622a80b..8c3dd7d 100644
--- a/src/test/java/de/ids_mannheim/korap/search/TestKrill.java
+++ b/src/test/java/de/ids_mannheim/korap/search/TestKrill.java
@@ -1,35 +1,31 @@
 package de.ids_mannheim.korap.search;
 
-import java.util.*;
-import java.io.*;
+import static de.ids_mannheim.korap.TestSimple.getString;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNull;
 
-import static de.ids_mannheim.korap.TestSimple.*;
+import java.io.IOException;
+import java.util.HashMap;
 
-import de.ids_mannheim.korap.Krill;
-import de.ids_mannheim.korap.KrillMeta;
-import de.ids_mannheim.korap.KrillCollection;
-import de.ids_mannheim.korap.KrillQuery;
-import de.ids_mannheim.korap.KrillIndex;
-import de.ids_mannheim.korap.query.QueryBuilder;
-import de.ids_mannheim.korap.index.FieldDocument;
-import de.ids_mannheim.korap.collection.CollectionBuilder;
-import de.ids_mannheim.korap.response.SearchContext;
-import de.ids_mannheim.korap.response.Result;
-import java.nio.file.Files;
-import java.nio.file.FileSystem;
-import java.nio.file.Path;
-import java.nio.charset.StandardCharsets;
-import java.nio.ByteBuffer;
-
-import com.fasterxml.jackson.databind.ObjectMapper;
-import com.fasterxml.jackson.databind.JsonNode;
-
-import static org.junit.Assert.*;
 import org.junit.Test;
-import org.junit.Ignore;
 import org.junit.runner.RunWith;
 import org.junit.runners.JUnit4;
 
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectMapper;
+
+import de.ids_mannheim.korap.Krill;
+import de.ids_mannheim.korap.KrillCollection;
+import de.ids_mannheim.korap.KrillIndex;
+import de.ids_mannheim.korap.KrillMeta;
+import de.ids_mannheim.korap.collection.CollectionBuilder;
+import de.ids_mannheim.korap.index.FieldDocument;
+import de.ids_mannheim.korap.query.QueryBuilder;
+import de.ids_mannheim.korap.response.Match;
+import de.ids_mannheim.korap.response.Result;
+import de.ids_mannheim.korap.response.SearchContext;
+
 @RunWith(JUnit4.class)
 public class TestKrill {
     @Test
@@ -635,6 +631,14 @@
         Result kr = ks.apply(ki);
         assertEquals(kr.getSerialQuery(),
                 "focus(1: spanContain(<tokens:base/s:s />, {1: tokens:s:Leben}))");
+        assertEquals(40, kr.getMatch(0).getStartPos());
+        assertEquals(41, kr.getMatch(0).getEndPos());
+
+        for (Match km : kr.getMatches()) {
+            System.out.println(km.getStartPos() + "," + km.getEndPos() + " "
+                    + km.getSnippetBrackets());
+        }
+
         assertEquals(
                 kr.getMatch(0).getSnippetBrackets(),
                 "... Initiative\" eine neue politische Gruppierung ins "
diff --git a/src/test/resources/queries/relation/focus-empty-both.json b/src/test/resources/queries/relation/focus-empty-both.json
new file mode 100644
index 0000000..1e9fa16
--- /dev/null
+++ b/src/test/resources/queries/relation/focus-empty-both.json
@@ -0,0 +1,39 @@
+{
+    "query": {
+        "@type": "koral:reference",
+        "operation": "operation:focus",
+        "classRef": [2],
+        "operands": [{
+            "@type": "koral:group",
+            "operation": "operation:relation",
+            "operands": [
+                {
+                   "@type": "koral:group",
+                    "operation": "operation:class",
+                    "classOut": 1,
+                    "operands": [{
+                        "@type": "koral:token"
+                    }]
+                },
+                {
+                    "@type": "koral:group",
+                    "operation": "operation:class",
+                    "classOut": 2,
+                    "operands": [{
+                        "@type": "koral:token"
+                    }]
+                }
+            ],
+            "relation": {
+                "@type": "koral:relation",
+                "wrap": {
+                    "@type": "koral:term",
+                    "foundry": "mate",
+                    "layer": "d",
+                    "key": "HEAD"
+                }
+            }
+        }]
+    },
+    "meta": {}
+}
diff --git a/src/test/resources/queries/relation/focus-empty-target.json b/src/test/resources/queries/relation/focus-empty-target.json
new file mode 100644
index 0000000..78ac125
--- /dev/null
+++ b/src/test/resources/queries/relation/focus-empty-target.json
@@ -0,0 +1,42 @@
+{
+    "query": {
+        "@type": "koral:reference",
+        "operation": "operation:focus",
+        "classRef": [2],
+        "operands": [{
+            "@type": "koral:group",
+            "operation": "operation:relation",
+            "operands": [
+                {
+                   "@type": "koral:group",
+                    "operation": "operation:class",
+                    "classOut": 1,
+                    "operands": [{
+                        "@type": "koral:span",
+                        "layer": "c",
+                        "key": "s",
+                        "match": "match:eq"
+                    }]
+                },
+                {
+                    "@type": "koral:group",
+                    "operation": "operation:class",
+                    "classOut": 2,
+                    "operands": [{
+                        "@type": "koral:token"
+                    }]
+                }
+            ],
+            "relation": {
+                "@type": "koral:relation",
+                "wrap": {
+                    "@type": "koral:term",
+                    "foundry": "mate",
+                    "layer": "d",
+                    "key": "HEAD"
+                }
+            }
+        }]
+    },
+    "meta": {}
+}
diff --git a/src/test/resources/queries/relation/focus-source.json b/src/test/resources/queries/relation/focus-source.json
index d934a3b..68d5ce4 100644
--- a/src/test/resources/queries/relation/focus-source.json
+++ b/src/test/resources/queries/relation/focus-source.json
@@ -11,8 +11,15 @@
                     "@type": "koral:token"
                 },
                 {
-                    "@type": "koral:span",
-                    "key": "np"
+                   "@type": "koral:group",
+                    "operation": "operation:class",
+                    "classOut": 1,
+                    "operands": [{
+                        "@type": "koral:span",
+                        "layer": "c",
+                        "key": "np",
+                        "match": "match:eq"
+                    }]
                 }
             ],
             "relation": {
diff --git a/src/test/resources/queries/relation/focus-target.json b/src/test/resources/queries/relation/focus-target.json
index daec972..46282a8 100644
--- a/src/test/resources/queries/relation/focus-target.json
+++ b/src/test/resources/queries/relation/focus-target.json
@@ -8,11 +8,26 @@
             "operation": "operation:relation",
             "operands": [
                 {
-                    "@type": "koral:span",
-                    "key": "s"
+                   "@type": "koral:group",
+                    "operation": "operation:class",
+                    "classOut": 1,
+                    "operands": [{
+                        "@type": "koral:span",
+                        "layer": "c",
+                        "key": "s",
+                        "match": "match:eq"
+                    }]
                 },
                 {
-                    "@type": "koral:token"
+                    "@type": "koral:group",
+                    "operation": "operation:class",
+                    "classOut": 2,
+                    "operands": [{
+                        "@type": "koral:span",
+                        "layer": "c",
+                        "key": "np",
+                        "match": "match:eq"
+                    }]
                 }
             ],
             "relation": {