diff --git a/1-js/07-object-oriented-programming/08-class-patterns/article.md b/1-js/07-object-oriented-programming/08-class-patterns/article.md
index c862d907..92fcd164 100644
--- a/1-js/07-object-oriented-programming/08-class-patterns/article.md
+++ b/1-js/07-object-oriented-programming/08-class-patterns/article.md
@@ -76,7 +76,7 @@ Like this:
 function User(name, birthday) {
   // only visible from other methods inside User
   function calcAge() {
-    new Date().getFullYear() - birthday.getFullYear();
+    return new Date().getFullYear() - birthday.getFullYear();
   }
 
   return {