Extend final grammar

psGrammar/tasks/final/final.jsgf

 #JSGF V1.0;
 grammar final;
-public <string> = [<robot>] (<bring> | <trash>);
+public <string> = [<robot>] (<bring> | <trash> | <door>);
 
 <bring> = [<prefix>] <drink>;
 
@@ -10,4 +10,6 @@ public <string> = [<robot>] (<bring> | <trash>);
 
 <drink> = (drink);
 
+<door> = ( ((go to the) | (get to the) | (take the) | (open the)) (door) );
+
 <robot> = (tobi) | (robot) | (biron) | (pepper);