diff --git a/src/main/java/org/ids_mannheim/SlidingWindowQueue.java b/src/main/java/org/ids_mannheim/SlidingWindowQueue.java
new file mode 100644
index 0000000..4f07362
--- /dev/null
+++ b/src/main/java/org/ids_mannheim/SlidingWindowQueue.java
@@ -0,0 +1,23 @@
+package org.ids_mannheim;
+
+import java.util.LinkedList;
+import java.util.function.Consumer;
+
+public class SlidingWindowQueue extends LinkedList {
+    private final int maxSize;
+    private final Consumer<String> flush;
+
+    public SlidingWindowQueue(int size, Consumer<String> flush) {
+        this.maxSize = size;
+        this.flush = flush;
+    }
+
+    public boolean add(String k) {
+        boolean r = super.add(k);
+        if (size() == maxSize) {
+            this.flush.accept(String.join(" ", this));
+            remove(0);
+        }
+        return r;
+    }
+}
diff --git a/src/main/java/org/ids_mannheim/TotalNGram.java b/src/main/java/org/ids_mannheim/TotalNGram.java
index 6db5308..a56580f 100644
--- a/src/main/java/org/ids_mannheim/TotalNGram.java
+++ b/src/main/java/org/ids_mannheim/TotalNGram.java
@@ -34,6 +34,11 @@
     int max_threads = MAX_THREADS;
 
     @SuppressWarnings("CanBeFinal")
+    @CommandLine.Option(names = {"-n",
+            "--ngram-size"}, description = "n-gram size (default: ${DEFAULT-VALUE})")
+    int ngram_size = 1;
+
+    @SuppressWarnings("CanBeFinal")
     @CommandLine.Option(names = {"-f",
             "--folds"}, description = "number of folds (default: ${DEFAULT-VALUE})")
     int FOLDS = 10;
@@ -55,7 +60,7 @@
         BlockingQueue<Integer> queue = new LinkedBlockingQueue<>(inputFiles.size());
         ExecutorService es = Executors.newCachedThreadPool();
         int threads = Math.min(max_threads, inputFiles.size());
-        IntStream.range(0, threads).forEach(unused -> es.execute(new Worker(queue, inputFiles, FOLDS, map, etaPrinter)));
+        IntStream.range(0, threads).forEach(unused -> es.execute(new Worker(queue, inputFiles, ngram_size, FOLDS, map, etaPrinter)));
         queue.addAll(IntStream.range(0, inputFiles.size()).boxed().collect(Collectors.toList()));
         IntStream.range(0, threads).forEach(unused -> {
             try {
diff --git a/src/main/java/org/ids_mannheim/Worker.java b/src/main/java/org/ids_mannheim/Worker.java
index 0619233..5bf951b 100644
--- a/src/main/java/org/ids_mannheim/Worker.java
+++ b/src/main/java/org/ids_mannheim/Worker.java
@@ -19,11 +19,13 @@
     private final ConcurrentHashMap<String, FoldedEntry> map;
     private final int folds;
     private final ETAPrinter etaPrinter;
+    private final int ngram_size;
 
-    public Worker(BlockingQueue<Integer> queue, ArrayList<String> fnames, int folds, ConcurrentHashMap<String, FoldedEntry> map, ETAPrinter etaPrinter) {
+    public Worker(BlockingQueue<Integer> queue, ArrayList<String> fnames, int ngram_size, int folds, ConcurrentHashMap<String, FoldedEntry> map, ETAPrinter etaPrinter) {
         this.queue = queue;
         this.fnames = fnames;
         this.map = map;
+        this.ngram_size = ngram_size;
         this.folds = folds;
         this.etaPrinter = etaPrinter;
     }
@@ -45,19 +47,24 @@
                 BufferedReader in = new BufferedReader(new InputStreamReader(p.getInputStream()));
                 String line;
                 int fold = -1;
+                SlidingWindowQueue slidingWindowQueue = null;
                 while ((line = in.readLine()) != null) {
                     if (line.startsWith("#")) {
                         Matcher matcher = new_text_pattern.matcher(line);
                         if (matcher.find()) {
                             fold = Math.abs(matcher.group(1).hashCode()) % folds +1;
                         }
+                        int finalFold = fold;
+                        slidingWindowQueue = new SlidingWindowQueue(ngram_size, s -> {
+                            FoldedEntry.incr(map, s, finalFold);
+                        });
                         continue;
                     }
                     String[] strings = line.split("\\s+");
                     if (strings.length < 4) {
                         continue;
                     }
-                    FoldedEntry.incr(map, strings[1], fold);
+                    slidingWindowQueue.add(strings[1]);
                 }
                 etaPrinter.update(file_size);
                 index = queue.take();