anchor.diff:  
   :marked
     ### NgForm and template reference variables
  +
     ### NgForm和模板引用变量
  +
     Let's look at one final example: a form, the poster child for template reference variables.
   
     让我们看看最后一个例子：一个表单，使用模板引用变量的典范。
  
positive.code: <a id="ngForMicrosyntax"></a>
  :marked
    #### NgFor microsyntax
    #### NgFor微语法
    The string assigned to `*ngFor` is not a [template expression](#template-expressions).
    It’s a *microsyntax* &mdash; a little language of its own that Angular interprets. In this example, the string `"let hero of heroes"` means:
  
  
negative.code:     我们既可以通过装饰器，又可以通过元数据数组来指定输入/输出属性。但别同时用！
  :marked
    ### Input or output?
  
    ### 输入或输出？
  
    *Input* properties usually receive data values.
  