Update article.md (#1517)

Update article.md

Author: lex111

1-js/09-classes/07-mixins/article.md

@@ -101,7 +101,7 @@ Here's the diagram (see the right part):
 
 ![](mixin-inheritance.svg)
 
-That's because methods `sayHi` and `sayBye` were initially created in `sayHiMixin`. So even though they got copied, their `[[HomeObject]]` internal property references `sayHiMixin`, as shown on the picture above.
+That's because methods `sayHi` and `sayBye` were initially created in `sayHiMixin`. So even though they got copied, their `[[HomeObject]]` internal property references `sayHiMixin`, as shown in the picture above.
 
 As `super` looks for parent methods in `[[HomeObject]].[[Prototype]]`, that means it searches `sayHiMixin.[[Prototype]]`, not `User.[[Prototype]]`.
 
@@ -112,7 +112,7 @@ Now let's make a mixin for real life.
 An important feature of many browser objects (for instance) is that they can generate events. Events are a great way to "broadcast information" to anyone who wants it. So let's make a mixin that allows us to easily add event-related functions to any class/object.
 
 - The mixin will provide a method `.trigger(name, [...data])` to "generate an event" when something important happens to it. The `name` argument is a name of the event, optionally followed by additional arguments with event data.
-- Also the method `.on(name, handler)` that adds `handler` function as the listener to events with the given name. It will be called when an event with the given `name` triggers, and get the arguments from `.trigger` call.
+- Also the method `.on(name, handler)` that adds `handler` function as the listener to events with the given name. It will be called when an event with the given `name` triggers, and get the arguments from the `.trigger` call.
 - ...And the method `.off(name, handler)` that removes the `handler` listener.
 
 After adding the mixin, an object `user` will be able to generate an event `"login"` when the visitor logs in. And another object, say, `calendar` may want to listen for such events to load the calendar for the logged-in person.