Spelling

Fixed some more minor spelling errors

6-async/02-promise-basics/article.md

@@ -34,7 +34,7 @@ When the executor finishes the job, it should call one of:
 - `resolve(value)` -- to indicate that the job finished successfully:
     - sets `state` to `"fulfilled"`,
     - sets `result` to `value`.
-- `reject(error)` -- to indicate that an error occured:
+- `reject(error)` -- to indicate that an error occurred:
     - sets `state` to `"rejected"`,
     - sets `result` to `error`.
 
@@ -128,7 +128,7 @@ The syntax of `.then` is:
 
 ```js
 promise.then(
-  function(result) { /* handle a sucessful result */ },
+  function(result) { /* handle a successful result */ },
   function(error) { /* handle an error */ }
 );
 ```

6-async/03-promise-chaining/article.md

@@ -207,7 +207,7 @@ class Thenable {
   }
   then(resolve, reject) {
     alert(resolve); // function() { native code }
-    // resolve with this.num*2 after the 1 secound
+    // resolve with this.num*2 after the 1 second
     setTimeout(() => resolve(this.num * 2), 1000); // (**)
   }
 }
@@ -513,7 +513,7 @@ new Promise(function(resolve, reject) {
   /* never runs here */
 }).catch(error => { // (**)
 
-  alert(`The unknown error has occured: ${error}`);
+  alert(`The unknown error has occurred: ${error}`);
   // don't return anything => execution goes the normal way
 
 });

6-async/05-async-await/article.md

@@ -295,4 +295,4 @@ The `await` keyword before a promise makes JavaScript wait until that promise se
 
 Together they provide a great framework to write asynchronous code that is easy both to read and write.
 
-With `async/await` we rarely need to write `promise.then/catch`, but we still shouldn't forget that they are based on promises, because sometimes (e.g. in the outmost scope) we have to use these methods. Also `Promise.all` is a nice thing to wait for many tasks simultaneously.
+With `async/await` we rarely need to write `promise.then/catch`, but we still shouldn't forget that they are based on promises, because sometimes (e.g. in the outermost scope) we have to use these methods. Also `Promise.all` is a nice thing to wait for many tasks simultaneously.