（新教材）《人教版》20版《高中全程学习方略》必修二课件：UNIT 3 DISCOVERING USEFUL STRUCTURES（英语） .ppt

1、Unit 3The InternetDiscovering Useful Structures现在完成时的被动语态【情境探究】观察下面句子,体会黑体部分的用法。1.Much has been written about the wonders of the World Wide Web.2.Peoples lives have been changed by online communities and social networks.3.Jans life has been greatly improved by the Internet.结论:观察以上句子可以得出,这一语法是现在完成时的被

2、动语态,其一般构成是_。have/has been done【要义详析】.现在完成时的被动语态的2个用法1.表示动作已经完成,强调对现在造成的影响或结果,经常与一些副词连用如already,ever,never,recently,lately,just,yet等,通常把这些副词放在助动词have或has的后面,有时候也可以放在句末。Toms novel has not been published yet.汤姆的小说还没有出版。2.表示一直持续到现在的动作或状态,经常与for a time,since,how long,so far等表示一段时间的时间状语连用。The child has be

3、en taken care of by grandma all these years.这些年来,孩子一直由奶奶照看。【名师点津】现在完成时的被动语态有两个助动词,就是have/has和been,这两个都是助动词,缺一不可。.现在完成时的被动语态与一般过去时的被动语态的区别一般过去时的被动语态表示的是一个被动的动作发生在过去某个时候,它的结果对现在没有影响;而现在完成时的被动语态,动作或状态尽管发生在过去,但强调这个动作或状态对现在造成的影响和结果。*The house was built last year.这个房子是去年建造的。*The house has been built.We ca

4、n move in.这个房子已经建好了。我们可以搬进去。.几点注意事项1.由finish,buy,start,begin,post,return,borrow,marry,open等词构成的现在完成时的被动语态,不能与表示一段时间的状语如for four days,how long等连用,而要改换动词或者是时态。试比较:*How long has this book been bought?(X)*How long ago was this book bought?()2.短语动词不能分割,而且不能省略短语动词中的介词或副词。试比较:*The patient has been taken go

5、od care.(X)*The patient has been taken good care of.()3.并不是所有的动词都有被动语态。如happen,occur,take place,break out,belong to,cost,last等不及物动词或词组,就没有被动语态。试比较:*Some of the best conversations have ever been happened around the dinner table.(X)*Some of the best conversations have ever happened around the dinner t

6、able.()【知识延伸】常见的其他被动语态1.一般现在时的被动语态am/is/are+done2.一般过去时的被动语态was/were+done3.情态动词的被动语态can/may/must/should be done 4.一般将来时的被动语态will/shall/be going to be+done【即学活用】将下列句子变为被动语态1.We have received many letters since last week.世纪金榜导学号_ 2.My friend has bought a new personal computer._ Many letters have been

7、received since last week.A new personal computer has been bought by myfriend.3.The shop has repaired my computer very quickly._ 4.An unknown virus has just attacked my computer._ My computer has been repaired by the shop veryquickly.My computer has just been attacked by an unknownvirus.5.The computer has replaced the machine._The machine has been replaced by the computer.