Added clarification

The solution explanation is not very obvious so added another example to make things clear

1-js/04-object-basics/04-object-methods/4-object-property-this/solution.md

@@ -22,6 +22,17 @@ The value of `this` is one for the whole function, code blocks and object litera
 
 So `ref: this` actually takes current `this` of the function.
 
+We can rewrite the function and return the same `this` with `undefined` value: 
+
+```js run
+function makeUser(){
+  return this; // this time there's no object literal
+}
+
+alert( makeUser().name ); // Error: Cannot read property 'name' of undefined
+```
+As you can see the result of `alert( makeUser().name )` is the same as `alert( user.ref.name )`
+
 Here's the opposite case:
 
 ```js run