2018-2019学年度人教版必修二Unit3ComputersPeriod FourGrammar-The Present Perfect Passive Voice

课文原句感知

1．Over time I have been changed(change) quite a lot.

2．First as a PC (personal computer) and then as a laptop，I have been used(use) in offices and homes since the 1970s.

3．Over time my memory has developed so much that，like an elephant，I never forget anything I have been told(tell)!

4．Since the 1970s many new applications have been found(find) for me.

5．I have also been put(put) into robots and used to make mobile phones as well as help with medical operations.

　　现在完成时的被动语态表示到现在为止某事已经被完成或被做。这种语法项目既要表示现在已经完成又要表示被动的含义，因此很多同学在具体运用当中容易顾此失彼，难以把握。

　　运用现在完成时的被动语态时应掌握以下几个问题：

1．构成

现在完成时的被动语态的构成为：have/has been＋过去分词。

2．各种句式

肯定式 主语＋have/has been done... 否定式 主语＋have/has not been done... 一般疑问式 Have/Has＋主语＋been done...？ 特殊疑问式 疑问词＋have/has＋主语＋been done...？