diff --git a/ps-grammar/demoChallenge/commands.jsgf b/ps-grammar/demoChallenge/commands.jsgf
index bfe7ed8d56867f1e2770ba2655f12eeb57d55535..8a0bb12f6f25a6eae887d081d6ebe455d48041a2 100644
--- a/ps-grammar/demoChallenge/commands.jsgf
+++ b/ps-grammar/demoChallenge/commands.jsgf
@@ -4,5 +4,5 @@ public <statement> = [tobi] [please] <command> [please] [tobi];
 
 <command> = <clean> | <party>;
 <clean> = clean up | start cleaning;
-<party> = party starts | party begining;
+<party> = party starts | party beginning;