diff --git a/exercises/enums/enums3.rs b/exercises/enums/enums3.rs
index 55acf6b..54fd6f6 100644
--- a/exercises/enums/enums3.rs
+++ b/exercises/enums/enums3.rs
@@ -52,7 +52,7 @@ mod tests {
             position: Point { x: 0, y: 0 },
             color: (0, 0, 0),
         };
-        state.process(Message::ChangeColor((255, 0, 255)));
+        state.process(Message::ChangeColor((255, 0, 255))); // Remember: The extra parentheses mark a tuple type.
         state.process(Message::Echo(String::from("hello world")));
         state.process(Message::Move(Point { x: 10, y: 15 }));
         state.process(Message::Quit);