diff --git a/ps-grammar/demoChallenge/commands.jsgf b/ps-grammar/demoChallenge/commands.jsgf
index cc1192d29ec462b67ebb89cee69b9957da1102fa..45d576050d9167c3d21c010d9b1a7df09da7de7f 100644
--- a/ps-grammar/demoChallenge/commands.jsgf
+++ b/ps-grammar/demoChallenge/commands.jsgf
@@ -1,9 +1,10 @@
 #JSGF V1.0;
 grammar bebot_demo;
-public <statement> = [tobi] [please] ( <command> | <teach> ) [please] [tobi];
+public <statement> = [tobi] [please] <command> [please] [tobi];
 
-<command> = <clean> | <party>;
+<command> = <clean> | <party> | <teach> | <mapping>;
 <clean> = clean up | start cleaning;
+<mapping> = start mapping;
 <party> = [the] party starts | party beginning;
 <teach> = ( (this is [a | an | the] ) | ( these are [the] ) ) <object>;
 <object> = [other] ( trashbin  );