diff --git a/en/application-dev/database/database-preference-guidelines.md b/en/application-dev/database/database-preference-guidelines.md
index e5c9faa1477565541a94076e2fb568e69b2f5cf6..724e273675061c4b6969fb3fcd6f6cbdd984a15f 100644
--- a/en/application-dev/database/database-preference-guidelines.md
+++ b/en/application-dev/database/database-preference-guidelines.md
@@ -114,21 +114,19 @@ You can use the following APIs to delete a **Preferences** instance or data file
    ```ts
    // Obtain the context.
    import UIAbility from '@ohos.app.ability.UIAbility';
-   let context = null;
    let preferences = null;
    export default class EntryAbility extends UIAbility {
-       onWindowStageCreate(windowStage){
-           context = this.context;
+       onWindowStageCreate(windowStage) {
+           let promise = data_preferences.getPreferences(this.context, 'mystore');
+            promise.then((pref) => {
+                preferences = pref;
+            }).catch((err) => {
+                console.info("Failed to get the preferences.");
+            })
        }
    }
    
-   let promise = data_preferences.getPreferences(context, 'mystore');
    
-   promise.then((pref) => {
-       preferences = pref;
-   }).catch((err) => {
-       console.info("Failed to get the preferences.");
-   })
    ```
 
 3. Write data.
diff --git a/en/application-dev/reference/apis/js-apis-data-preferences.md b/en/application-dev/reference/apis/js-apis-data-preferences.md
index de22c34d2a99d3e7391061cc9233089409944599..b14256c20d12c8fedd2bb6d8f0b7f38091bbc8d5 100644
--- a/en/application-dev/reference/apis/js-apis-data-preferences.md
+++ b/en/application-dev/reference/apis/js-apis-data-preferences.md
@@ -22,8 +22,8 @@ import data_preferences from '@ohos.data.preferences';
 
 | Name            | Type| Readable| Writable| Description                                   |
 | ---------------- | -------- | ---- | ---- | --------------------------------------- |
-| MAX_KEY_LENGTH   | number   | Yes  | No  | Maximum length of a key. The key must be less than 80 bytes.    |
-| MAX_VALUE_LENGTH | number   | Yes  | No  | Maximum length of a value. The value must be less than 8192 bytes.|
+| MAX_KEY_LENGTH   | number   | Yes  | No  | Maximum length of a key. The maximum key length is 80 bytes.    |
+| MAX_VALUE_LENGTH | number   | Yes  | No  | Maximum length of a value. The maximum value length is 8192 bytes.|
 
 
 ## data_preferences.getPreferences