Update README.md

Author: hoc081098

README.md

@@ -14,11 +14,12 @@ Reactive storage for Dart/Flutter. RxDart Storage for Dart/Flutter.
 ## Note: [rx_shared_preferences](https://github.com/hoc081098/rx_shared_preferences) is an extension of this package.
 
 ## More detail about returned `Stream`
+
 -   It's a **single-subscription `Stream`** (ie. it can only be listened once).
 
 -   `Stream` will emit the **value (nullable)** or **a `TypeError`** as its first event when it is listen to.
 
--   It will automatic emits value when value associated with key was changed successfully
+-   It will automatically emit value when value associated with key was changed successfully
     (**emit `null`** when value associated with key was `removed` or set to `null`).
 
 -   When value read from Storage has a type other than expected type:
@@ -27,10 +28,10 @@ Reactive storage for Dart/Flutter. RxDart Storage for Dart/Flutter.
 
 -   **Can emit** two consecutive data events that are equal. You should use Rx operator like `distinct` (More commonly known as `distinctUntilChanged` in other Rx implementations) to create an `Stream` where data events are skipped if they are equal to the previous data event.
 
-```
-Key changed:  |----------K1---K2------K1----K1-----K2---------
+```text
+Key changed:  |----------K1---K2------K1----K1-----K2---------> time
               |                                                
-Value stream: |-----@----@------------@-----@-----------------
+Value stream: |-----@----@------------@-----@-----------------> time
               |    ^                                      
               |    |
               |  Listen(key=K1)