diff --git a/pages/manual/planet.md b/pages/manual/planet.md
index 597abc3..a4c889d 100755
--- a/pages/manual/planet.md
+++ b/pages/manual/planet.md
@@ -143,6 +143,8 @@ By clicking on "Title", or "Rating", you are able to sort the course list accord
 
 * Action Menu
 
+By clicking the checkbox left of a course, you are able to use action menu.
+
 ![Menu](images/courses-menu.png)
 
 The action menu has several different actions available.