高中英语 Unit 3 Computers Section Three Grammar课件.pptx

Unit3Computers,TwoTasks:ThePresentPerfectTenseThePresentPerfectPassiveVoice,ThePresentPerfectTense,现在完成时,Iboughtanewcartwoweeksago.,Ihaveboughtanewcar.,(两周以前购买，动作发生于过去。),(“我”“已经购买”，“已经拥有”，重在强调“有”的结果与影响。),Ihadmylunchattwelveoclock.,Ihavehadmylunch.,(我在12点吃的午饭。),(我已经吃了午饭。),ThePresentPerfectTense,含义I,1.表示过去已经发生或已经完成的某一动作对现在造成的影响或结果.,2.不仅单纯表示一个过去的动作，而且还表示该动作对现在的某种影响以及产生的后果；既涉及过去，又联系现在。即现在完成时的动作并非“现在”完成，而是“过去”完成，并重在强调动作完成的结果与影响。,e.g.Wehaveseenthenewfilm.,构成：,ThePresentPerfectTense,have/has+P.P.,Note:P.P.pastparticiple过去分词,e.g.Iveseenthisfilm.,Hehaslosthismathbook.,ThePresentPerfectTense,过去分词的构成：,一般动词，在词尾直接加“-ed”。,以“e”结尾的动词，只在词尾加“-d”。,以“辅音字母+y”结尾的动词，将“y”变为“i”，再加“-ed”。,重读闭音节结尾，末尾只有一个辅音字母，先双写该辅音字母，再加“-ed”。,规则动词：规则动词的过去分词的构成规则与规则动词的过去式的构成规则相同。,work,visit,live,study,cry,play,stop,drop,不规则动词：不规则动词的过去分词要特别牢记，详见课后附录中的不规则动词表。,ThePresentPerfectTense,句式变化：,1)肯定句：,have/has+P.P.,2)否定句：,have/has+_+P.P.,not,3)一般疑问句：,Haveyoudoneyourhomework?,Icamehereeightyearsago.,Ihavelivedhereforeightyears.,Ihavelivedheresinceeightyearsago.,我8年前来到这儿。,我在这儿住了已经8年了。,我自从8年前就住在这儿。,表示过去已经开始，持续到现在的动作或状态，可以和表示从过去某一时刻延续到现在（包括“现在”在内）的一段时间的状语连用。,ThePresentPerfectTense,含义II,连用的时间状语：,ThePresentPerfectTense,for+一段时间,since+过去时间点/过去动作点（从句）,Ihavelivedhereforeightyears.,Ihavelivedheresinceeightyearsago.,Ihavelivedheresince1981.,ThePresentPerfectPassiveVoice,现在完成时的被动语态,ThePresentPerfectPassiveVoice,构成：,have/has+_+done,been,主动变被动：,Wehaveusedeverypossiblemeanstopreventtheairpollution.,Everypossiblemeans_topreventtheairpollution.,hasbeenused,Exercises1.Bothmybrotherworkatthepowerstationthat_inmyhometown.A.hassetupB.hasbeensetupC.wassetupD.issetup2.-_thesportsmeetwillbeputoff.A.IvebeentoldB.IvetoldC.ImtoldD.Itold3.Allthepreparationforthetask_,andwerereadytostart.A.completedB.completeC.hadbeencompletedD.havebeendone4.-Howlong_atthisjob?-Since1990.A.wereyouemployedB.haveyoubeenemployedC.hadyoubeenemployedD.willyoubeemployed,B,A,D,B,5.Whenandwheretogofortheon-salaryholiday_yet.A.arenotdecidedB.havenotbeendecidedC.isnotbeingdecidedD.hasnotbeendecided,B,6.Nopermissionhas_foranybodytoenterthebuilding.（MET1988）A.beengivenB.givenC.togiveD.begiving,A,7.Untilnow,hishomeworkhasnot_finished.A.beingB.beC.beenD.tobe,C,8.Thewindows_,youneednotwashitagain.A.iswashedB.waswashedC.hasbeenwashe