diff --git a/1-js/07-object-oriented-programming/09-class/article.md b/1-js/07-object-oriented-programming/09-class/article.md
index 549a40e1..f2303523 100644
--- a/1-js/07-object-oriented-programming/09-class/article.md
+++ b/1-js/07-object-oriented-programming/09-class/article.md
@@ -7,7 +7,7 @@ The "class" construct allows to define prototype-based classes with a clean, nic
 
 ## The "class" syntax
 
-The `class` syntax is versatile, we'll start from a simple example first.
+The `class` syntax is versatile, we'll start with a simple example first.
 
 Here's a prototype-based class `User`:
 
@@ -57,13 +57,13 @@ Here's the code to dig into the class and see that:
 ```js run
 class User {
   constructor(name) { this.name = name; }
-  sayHi() { alert(this.name);  }
+  sayHi() { alert(this.name); }
 }
 
 *!*
 // proof: User is the "constructor" function
 */!*
-alert(User == User.prototype.constructor); // true
+alert(User === User.prototype.constructor); // true
 
 *!*
 // proof: there are two methods in its "prototype"
@@ -129,7 +129,7 @@ class User {
   set name(value) {
 */!*
     if (value.length < 4) {
-      alert("Name too short.");
+      alert("Name is too short.");
       return;
     }
     this._name = value;
@@ -146,7 +146,7 @@ user = new User(""); // Name too short.
 Internally, getters and setters are also created on the `User` prototype, like this:
 
 ```js
-Object.defineProperty(User.prototype, {
+Object.defineProperties(User.prototype, {
   name: {
     get() {
       return this._name
@@ -239,7 +239,7 @@ class User {
 *!*
   static staticMethod() {
 */!*
-    alert(this == User);
+    alert(this === User);
   }
 }
 
@@ -252,7 +252,7 @@ That actually does the same as assigning it as a function property:
 function User() { }
 
 User.staticMethod = function() {
-  alert(this == User);
+  alert(this === User);
 };
 ```
 
@@ -312,7 +312,7 @@ class Article {
 *!*
   static createTodays() {
     // remember, this = Article
-    return new this("Todays digest", new Date());
+    return new this("Today's digest", new Date());
   }
 */!*
 }
@@ -322,7 +322,7 @@ let article = Article.createTodays();
 alert( article.title ); // Todays digest
 ```
 
-Now every time we need to create a todays digest, we can call `Article.createTodays()`. Once again, that's not a method of an article, but a method of the whole class.
+Now every time we need to create a today's digest, we can call `Article.createTodays()`. Once again, that's not a method of an article, but a method of the whole class.
 
 Static methods are also used in database-related classes to search/save/remove entries from the database, like this: