diff --git a/prompt_parser.py b/prompt_parser.py
index 7b1957c..1cc4679 100644
--- a/prompt_parser.py
+++ b/prompt_parser.py
@@ -14,7 +14,7 @@
 
 schedule_parser = lark.Lark(r"""
 !start: (prompt | /[][():]/+)*
-prompt: (emphasized | scheduled | alternate | plain | WHITESPACE)*
+prompt: (emphasized | scheduled | grouped | alternate | plain | WHITESPACE)*
 !emphasized: "(" prompt ")"
         | "(" prompt ":" prompt ")"
         | "[" prompt "]"