英语必修二人教版 Unit3 Computers2.3 grammar (共23张PPT).ppt

1、The Present Perfect Passive Voice现在完成时的被动语态现在完成时常与 already,always,often,ever,never,yet,not.yet,just等模糊的时间副词连用。还可以和表示跟现在有关的或者一直延续到现在的时间状语连用。如:now,today,this month,this year,lately recently,these few days,in the past 10 years,in the last few years,so far,up to now,ever since等。现在完成时态中的时间状语1.First as a

2、PC and then as a laptop,I _(use)in offices and homes since the 1970s.2.Over time my memory _(develop)so much that,like an elephant,I never forget anything I _(told).3.Since the 1970s many new applications _(find)for me.4.I have also _(put)into robots and used to make mobile phones as well as help wi

3、th medical operations.5.I _(put)into space rockets and sent to explore the Moon and Mars.课文内容复习：用动词正确形式填空have been usedhas developedhave been toldhave been foundbeen puthave even been put1.现在完成时的被动语态构成：主语是行为动作的承受者谓语动词表示动作已经完成例如：I have been told about it many timesThe bridge has just been builthave/h

4、as(not)+been+过去分词2.现在完成时的被动语态特点：Change the following sentences into the present perfect passive voice.(见课本P21)1.A new personal computer has been bought by my friend.2.My computer has been repaired by the shop very quickly.3.My computer has just been attacked by an unknown virus.5.The computers have

5、been given away to a local school by the company.4.The problem has not been solved by us yet.6.A kind of intelligent robot has been developed by the scientists.Exercises1.Both my brother work at the power station that _ in my hometown.A.has set up B.has been set up C.was set up D.is set up2.-_ the s

6、ports meet will be put off.A.Ive been told B.Ive told C.Im told D.I told3.All the preparation for the task _,and were ready to start.A.completed B.complete C.had been completed D.have been done4.-How long _ at this job?-Since 1990.A.were you employed B.have you been employed C.had you been employed

7、D.will you be employed5.When and where to go for the on-salary holiday _ yet.A.are not decided B.have not been decided C.is not being decided D.has not been decided6.Betty_ injured since last Saturday.A.has been B.was C.is D.has7.-Did you move into the new house?-No.The rooms _ yet.A.were being pain

8、ted B.are painting C.have not painted D.have not been painted 8.Great changes_ in my hometown and a lot of factories _.A.have been taken place;are being set up B.have taken place;have been set up C.are taken place;had been set up D.took place;will set up 改错1.A personal computer has bought by us.2.Ma

9、ny problems has been found with our new computer.Many problems have been found with our new computer.A personal computer has been bought by us.3.The computer was used every day since we bought it.The computer has been used every day since we bought it.4.A lot of e-mails had written on the computer i

10、n the past 5 years.A lot of e-mails have been written on the computern in the past 5 years.5.The house has been rebuilded the way we wanted.The house has been rebuilt the way we wanted.The accident has happened here.6.The accident has been happened here.1.脏衣服都已经洗了。The dirty clothes_.2.这项计划已经由专家改动过三次

11、了。The plan_by the experts for three times.3.我的电脑很快就被修理好了。My computer _very quickly.4.这个问题还没有解决。The problem _yet.Complete the following sentences：have been washed.has been changedhas been repairedhas not been solved现在完成时和一般过去时的区别Jane left an hour ago.Jane has left now.(她现在已经不在这里了。)He worked in the ho

12、spital for 7 years.(现在不在那个医院了)He has worked in that hospital for 7 years.（现在仍在那里工作）现在完成时强调过去的动作对现在有影响；一般过去时只表示过去某个具体时间里发生的动作，与现在没有联系。两者都可表示过去开始并延续了一段时间的动作，但现在完成时表示动作可能还要继续下去，而一般过去时则说明动作已经结束。时态的构成：一般过去时：现在完成时：have/has+过去分词被动语态的构成：一般过去时的被动语态：现在完成时的被动语态：have/has+been+过去分词用动词的过去式(was/were/did)表示was/were

13、+过去分词一般过去时常与具体的表示过去的时间状语连用，如yesterday,last week,two days ago,at 10:00,in 1980,in the 2020s等。还跟once,just now,in the other day(不久前的某一天)，in the past等模糊时间状语连用。一般过去时态中的时间状语改错1.I have finished reading this book three days ago.I finished reading this book three days ago.I have finished reading this book since three days ago.2.I have lost my watch just now.I lost my watch just now.I have just lost my watch.3.He walked to work in the past few years.He has walked to work in the past few years.He walked to work in the past.4.She has appeared at 3:00 this afternoon.She appeared at 3:00 this afternoon.