diff --git a/DESCRIPTION b/DESCRIPTION
index 3e42071..3b11c0a 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -1,7 +1,7 @@
 Package: kableExtra
 Type: Package
 Title: Construct Complex Table with 'kable' and Pipe Syntax
-Version: 0.2.0
+Version: 0.2.0.9000
 Authors@R: c(
     person('Hao', 'Zhu', email = 'haozhu233@gmail.com', role = c('aut', 'cre')),
     person('Will', 'Beasley', email = 'wibeasley@hotmail.com', role = 'ctb'),
diff --git a/R/column_spec.R b/R/column_spec.R
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/R/column_spec.R
diff --git a/README.md b/README.md
index 6e84787..d1ee5ae 100644
--- a/README.md
+++ b/README.md
@@ -75,3 +75,4 @@
 [x] A function to easily add title column indent
 [ ] Some ways to change text/background color of cells
 [ ] Find a way to let align table caption.
+[ ] Add `column_spec`
diff --git a/docs/awesome_table_in_pdf.Rmd b/docs/awesome_table_in_pdf.Rmd
index 467bc0f..fc47b0d 100644
--- a/docs/awesome_table_in_pdf.Rmd
+++ b/docs/awesome_table_in_pdf.Rmd
@@ -177,6 +177,7 @@
                  "Group 1 contains mpg, cyl and disp", 
                  "Group 2 contains hp, drat and wt"), 
                notation = "symbol") %>%
+  group_rows("Group 1", 4, 5) %>%
   landscape()
 ```
 
diff --git a/docs/awesome_table_in_pdf.pdf b/docs/awesome_table_in_pdf.pdf
index f11450f..b378f65 100644
--- a/docs/awesome_table_in_pdf.pdf
+++ b/docs/awesome_table_in_pdf.pdf
Binary files differ
diff --git a/docs/use_kable_in_shiny.Rmd b/docs/use_kable_in_shiny.Rmd
index 5cfcedb..c2af6bf 100644
--- a/docs/use_kable_in_shiny.Rmd
+++ b/docs/use_kable_in_shiny.Rmd
@@ -11,7 +11,7 @@
 knitr::opts_chunk$set(echo = TRUE)
 ```
 
-To use `knitr::kable()` and `kableExtra` in shiny couldn't be simpler. 
+Since the output is just HTML, it's very easy to use `kable` and `kableExtra` in the Shiny environment. For example:
 ```{r, eval = FALSE}
 library(shiny)
 
@@ -53,7 +53,7 @@
 
 ```
 
-To simply:
+You can copy/paste the code above or simply run:
 
 ```{r, eval=FALSE}
 shiny::runGist("https://gist.github.com/haozhu233/9e675e1a8a1bb4744f9ebc9246a2366b")
diff --git a/docs/use_kable_in_shiny.html b/docs/use_kable_in_shiny.html
index a34a13f..3cd06e5 100644
--- a/docs/use_kable_in_shiny.html
+++ b/docs/use_kable_in_shiny.html
@@ -120,7 +120,7 @@
 </div>
 
 
-<p>To use <code>knitr::kable()</code> and <code>kableExtra</code> in shiny couldn’t be simpler.</p>
+<p>Since the output is just HTML, it’s very easy to use <code>kable</code> and <code>kableExtra</code> in the Shiny environment. For example:</p>
 <pre class="r"><code>library(shiny)
 
 ui &lt;- fluidPage(
@@ -157,7 +157,7 @@
 
 # Run the application
 shinyApp(ui = ui, server = server)</code></pre>
-<p>To simply:</p>
+<p>You can copy/paste the code above or simply run:</p>
 <pre class="r"><code>shiny::runGist(&quot;https://gist.github.com/haozhu233/9e675e1a8a1bb4744f9ebc9246a2366b&quot;)</code></pre>
 
 
diff --git a/vignettes/use_kable_in_shiny.Rmd b/vignettes/use_kable_in_shiny.Rmd
index 5cfcedb..c2af6bf 100644
--- a/vignettes/use_kable_in_shiny.Rmd
+++ b/vignettes/use_kable_in_shiny.Rmd
@@ -11,7 +11,7 @@
 knitr::opts_chunk$set(echo = TRUE)
 ```
 
-To use `knitr::kable()` and `kableExtra` in shiny couldn't be simpler. 
+Since the output is just HTML, it's very easy to use `kable` and `kableExtra` in the Shiny environment. For example:
 ```{r, eval = FALSE}
 library(shiny)
 
@@ -53,7 +53,7 @@
 
 ```
 
-To simply:
+You can copy/paste the code above or simply run:
 
 ```{r, eval=FALSE}
 shiny::runGist("https://gist.github.com/haozhu233/9e675e1a8a1bb4744f9ebc9246a2366b")