anchor.diff:  
     We want to start the TypeScript compiler, have it watch for changes, and start our server. We'll do this by typing
   
  -  我们要启动TypeScript编译器，它会监视文件变更，并启动开发服务器。只要敲：
  +  我们要启动 TypeScript 编译器，它会监视文件变更，并启动开发服务器。只要敲：
   
   code-example(language="bash").
     npm start
  
positive.code:   At the moment, the *Heroes* and *Hero Detail* views are combined in one template in `AppComponent`.
    Let’s **cut** the *Hero Detail* content from `AppComponent` and **paste** it into the new template property of  `HeroDetailComponent`.
  
    目前，`AppComponent`的*英雄列表*和*英雄详情*视图被组合在同一个模板中。
    让我们从`AppComponent`中**剪切**出*英雄详情*的内容，并且粘贴到`HeroDetailComponent`组件的`template`属性中。
  
    We previously bound to the `selectedHero.name` property of the `AppComponent`.
    Our `HeroDetailComponent` will have a `hero` property, not a `selectedHero` property.
    So we replace `selectedHero` with `hero` everywhere in our new template. That's our only change.
    The result looks like this:
  
    以前我们绑定到了`AppComponent`的`selectedHero.name`属性中。
    `HeroDetailComponent`组件将会有一个`hero`属性，而不是`selectedHero`属性。
    所以，我们要把模板中的所有`selectedHero`替换为`hero`。只改这些就够了。
    最终结果如下所示：
  
negative.code:   especially if doing them right is easy and we learn how to build Angular apps in the process.
  
    我们当前的组件违反了[单一职责原则](https://blog.8thlight.com/uncle-bob/2014/05/08/SingleReponsibilityPrinciple.html)。
    虽然这只是一个教程，但我们还是得坚持做正确的事 &mdash;
    况且，做正确的事这么容易，在此过程中，我们又能学习如何构建 Angular 应用。
  
    Let’s break the hero details out into its own component.
  
  