anchor.diff:      ### NgForm指令
       What `NgForm` directive? We didn't add an [NgForm](../api/forms/index/NgForm-directive.html) directive!
   
  -    什么`NgForm`指令？之前没有添加过[NgForm](../api/common/index/NgForm-directive.html)指令啊！
  +    什么`NgForm`指令？之前没有添加过 [NgForm](../api/common/index/NgForm-directive.html) 指令啊！
   
       Angular did. Angular creates and attaches an `NgForm` directive to the `<form>` tag automatically.
   
  
positive.code:       No wonder Angular chose to combine the punctuation as <span style="font-family:courier"><b>[()]</b></span>
        to signify a two-way data binding and a **flow of data in both directions**.
  
        不出所料，Angular选择了组合标点 <span style="font-family:courier"><b>[()]</b></span> 来标记出双向数据绑定和**双向数据流**。
  
        In fact, we can break the `NgModel` binding into its two separate modes
        as we do in this re-write of the "Name" `<input>` binding:
  
        事实上，可以把`NgModel`绑定拆成两个独立的绑定，就像下面重写的“Name”`<input>`绑定一样：
    +makeExample('forms/ts/app/hero-form.component.html', 'ngModel-3','app/hero-form.component.html (excerpt)')(format=".")
  
    :marked
  
negative.code: 
    - build an Angular form with a component and template
  
      使用组件和模板构建 Angular 表单
  
    - two-way data bind with `[(ngModel)]` syntax for reading and writing values to input controls
  
  