diff --git a/psGrammar/confirm/confirm.jsgf b/psGrammar/confirm/confirm.jsgf
index 530ea50065a4ef17897aa549c3b5765f67bf8ce9..82c87122503d0d1db54842f194963d497b338599 100644
--- a/psGrammar/confirm/confirm.jsgf
+++ b/psGrammar/confirm/confirm.jsgf
@@ -2,9 +2,9 @@
 grammar ToBI_confirm;
 public <confirm> = <confirm_yes> | <confirm_no>;
 
-<confirm_yes> = <robot> <yes_words>;
-<confirm_no> = <robot> <no_words>; 
+<confirm_yes> = [<robot>] <yes_words>;
+<confirm_no> = [<robot>] <no_words>; 
 
 <yes_words> = (yes);
 <no_words> = (no);
-<robot> = (tiago);
+<robot> = (tiago, tobi);