fix: 精修翻译

aio/content/tutorial/toh-pt5.md

@@ -12,7 +12,7 @@ There are new requirements for the Tour of Heroes app:
 
 * Add the ability to navigate between the *Heroes* and *Dashboard* views.
 
-   在*英雄列表*和*仪表盘*视图之间导航。
+   添加在*英雄列表*和*仪表盘*视图之间导航的能力。
 
 * When users click a hero name in either view, navigate to a detail view of the selected hero.
 

aio/content/tutorial/toh-pt6.md

@@ -502,7 +502,7 @@ That header is in the `httpOptions` constant defined in the `HeroService`.
 Refresh the browser, change a hero name and save your change. Navigating to the previous view is implemented in the `save()` method defined in `HeroDetailComponent`.
 The hero now appears in the list with the changed name.
 
-刷新浏览器，修改英雄名，保存这些修改，然后点击“后退”按钮。
+刷新浏览器，修改英雄名，保存这些修改。在 `HeroDetailComponent` 的 `save()` 方法中实现了 "导航到前一个视图" 的逻辑。
 现在，改名后的英雄已经显示在列表中了。
 
 ## Add a new hero