fix

ps-grammar/sfb/review.jsgf

@@ -3,7 +3,7 @@ grammar A4_inspection;
 public <review> = [tobi] [please] (<follow> | <observe> | <teach> | <locate> | <list> | <leave> | <continue> | <stop> ) [please] [tobi];
 
 <follow> = ( follow me [into the elevator] );
-<observe> = (start observing | ([take a] look [(at this | here)] | observe ));
+<observe> = (start observing | observe | ([take a] look [(at this | here)] ));
 <leave> = leave;
 <continue> = continue;
 <stop> = (stop [observing | it]);