diff --git a/demos/gtk-demo/gltransition.c b/demos/gtk-demo/gltransition.c
index 7d51d32be4..b95ffc4d6d 100644
--- a/demos/gtk-demo/gltransition.c
+++ b/demos/gtk-demo/gltransition.c
@@ -10,7 +10,7 @@
  * GL areas and plain old widgets to demonstrate this.
  *
  * The demo also shows some over-the-top effects like wobbly widgets,
- * and a an animated background.
+ * and animated backgrounds.
  */
 
 #include <math.h>