高中英语语法虚拟语气讲解详解

语气英语的动词一般可带有三种不同的语气：陈述语气，祈使语气和虚拟语气。不同的语气用动词的不同形式（有的还借助句法形式）来表示。虚拟语气虚拟语气是一种特殊的动词形式，一是用来表示说话人所说的话不是一个事实，而是一种假设、猜测、怀疑等(在条件从句中或让步状语从句中)；一是表示说话人的愿望、要求、命令、建议等(在宾语从句、表语从句、同位语从句)。虚拟语气的概念一、虚拟语气在条件句中虚拟条件句主句与现在事实相反的假设与过去相反的假设与将来相反的假设If+主语+动词的过去式（动词be用were)主语+should,would,might,could＋动词原形If+主语+had+过去分词主语＋should,would,might,could＋havedoneIf+主语+动词过去式If+主语+wereto+动词原形If+主语+should+动词原形主语＋should,wouldmight,could＋动词原形eg:IfIhadtime,Iwouldattendthemeeting.Ifhehadhurried,hecouldhavecaughtthetrain.IfIweretogoabroad,IwouldgotoAmerica.如果我是你，我就会努力学习．如果我知道他的电话号码，我就给他打电话了．如果明天下雨的话，我们会取消比赛．IfIwereyou,Iwouldworkharderatmylessons.IfIhadknownhistelephonenumber,Iwouldhavecalledhim.Ifitshould\weretorain,wewouldcalloffthematch.Morepractice:c.Ifthepoliceman________(benot)inthatroom,it________(be)verydangerous.d.IfI____(be)inyourposition,I_________(ask)forteacher’shelp.werenotcouldbewerewouldaska.IfTom________(be)morecarefulintheexam,he________________(pass)italready.b.Ifyou_______(get)upearlier,you________________(catch)thefirsttrain.hadbeenwouldhavepassedhadgotwouldhavecaughtPRACTICE2:Fillintheblanks.a.Ifthere________(be)nonaturalresourceanymore,we___________(make)useofnuclearpower.b.What____________(happen)ifyou____________(getup)toolatetomorrow?shouldbeshouldmakewouldhappenshouldgetupPRACTICE3:Fillintheblanksc.IfRobots_____________(control)theworldsomeday,here________(be)nofriendship.weretocontrolwouldbe使用虚拟条件句要注意的几点：１．当条件状语从句表示的行为和主句表示的行为所发生的时间不一致时，被称为：错综时间条件句“，动词的形式要根据它所表示的时间作出相应的调整．Ifyou___________(follow)myadvice,you___________(be)betternow.如果你听我的建议，你现在就会痊愈了．hadfollowedwouldbeIfyouhadstudiedhardbefore,youwouldbeacollegestudentnow.如果你努力学习的话，你现在就会是大学生了．２．省略句在条件句中，可省略if，把were,had,should提到句首，变为倒装句式．IfIwereatschoolagain,Iwouldstudyharder.WereIatschoolagain,Iwouldstudyharder.Ifyouhadcomeearlier,youwouldhavemethim.Hadyoucomeearlier,youwouldhavemethim.Ifitshouldraintomorrow,wewouldnotgoclimbing.Shoulditraintomorrow,wewouldnotgoclimbing.二、虚拟语气在名词从句中的运用１、wish后面的宾语从句中。一般用虚拟语气，表示一种不可能实现的愿望。其谓语动词形式为：表现在过去时表过去过去完成时表将来would,might,could＋动词原形Iwish(that)Iwereabird.Iwish(that)Ihadseenthefilmlastnight.Iwish(that)Iwould\couldgo.2.Ifonly（要是．．．该有多好啊)表示现在的情况,应用过去式;如果是过去的情况,应用过去完成时态*ifonly通常独立使用，没有主句。IfonlyIknewtheanswer!IfonlyIhadseenthefilmyesterday!Ifonlyshewouldgowithme!3.asif(asthough)看起来常用虚拟形式，即表示与现在事实相反，用过去式；与过去事实相反用过去完成式(haddone).Hetreats/treatedtheboyasifhewerehisownson.Hespeaks/spokeasifhehadknownaboutit4.wouldrather+从句动词用过去式或过去完成时Iwouldratheryoutoldmethetruth.IwouldratheryouhadgonetherelastSunday.Iwouldratheryoucametomorrow.1.Itis(high/about)timethat…从句中的谓语动词用过去式或should＋动词原形，should不能省略．Itishightimethatyouwent/shouldgotoschool.2.Ifonly（要是．．．该有多好啊)表示现在的情况,应用过去式;如果是过去的情况,应用过去完成时态*ifonly通常独立使用，没有主句。IfonlyIknewtheanswer!IfonlyIhadseenthefilmyesterday!Ifonlyshewouldgowithme!2.用于表示命令、建议、要求等一类词后面的宾语从句。insist,order,command,suggest,advise,propose,require,request,demand,desireetc.Wesuggestedthatthemeeting(should)beputoff.Theyinsistedthattheboy(should)gowiththem.注意：suggest当表示“暗示、表明“讲时，insist表示”坚持认为“之意时，应用陈述语气。Thesmileonhisfacesuggestedthathewassatisfiedwithourwork.Themaninsistedthathehadneverstolenthemoney.他脸上的表情表明他对我们的工作很满意．那个人坚持说他没有偷钱．在suggestion/proposal/order/plan/advice/idea/request等名词后的表语和同位语从句中要用“should＋动词原形”should可以省略．（2）用于表语从句和同位语从句Myideaisthatwe(should)thinkitoverbeforeacceptingit.Mysuggestionthatwe(should)haveameetinghasbeenacceptedbyothers.Weallagreetothatsuggestionthatthemeeting(should)beputoff.A.在句型“Itisimportant(necessary,strange,natural)that....”中，that后面的从句中的谓语动词用：should+动词原形1.我们有必要出去散散步。It’snecessarythatweshouldhaveawalknow.2她这样做是很自然的。It’snaturalthatsheshoulddoso.3重要的是我们要照顾好病人。It’simportantthatweshouldtakegoodcareofthepatient.（3）虚拟语气在在主语从句中B.在Itisdemanded/suggested/ordered/required….that-clause句型中从句用(should)+动词原型Itisdemandedthatweshouldworkoutaplan.C.在Itisapity/ashame/nowonderthat…..句型中从句也常用(should)+动词原型It’sapitythatyou(should)missagoodchance.3.wouldrather+从句动词用过去式或过去完成时Iwouldratheryoutoldmethetruth.IwouldratheryouhadgonetherelastSunday.4.asif(asthough)看起来常用虚拟形式，即表示与现在事实相反，用过去式；与过去事实相反用过去完成式(haddone).Hetreats/treatedtheboyasifhewerehisownson.Hespeaks/spokeasifhehadknownaboutit5.evenif(eventhough)即使Evenifhewerehere,hecouldnotsolvetheproblem.EvenifIhadbeenbusythen,Iwouldhavehelpedyou.四情态动词+havedonecouldhavedone本来可以---mighthavedone本来可能---should/oughttohavedone本来应该做---shouldn’t/oughtnottohavedone本不该做--你本不应该告诉她真相。Youshouldn’thavetoldherthetruth.needn’thavedone本不必做---比较：didn’tneedtodo没必要做也没有做---我没必要擦窗户。我兄弟做了Ididn’tneedtocleanthewindows.Mybrotherdidit.wouldhavedone本来会去做----我没有足够的钱．否则我会买那本书的．Ididn’thaveenoughmoney,otherwiseIwouldhaveboughtthatbook.虚拟语气3.一些介词短语,如:butfor(要不是),without,otherwise(否则),inthatcase(如果是那样的话),表示含蓄的条件,这时主句要用虚拟语气Withoutyourhelp,wewouldnothavemadesuchrapidprogress.虚拟语气中的几个特例III.用括号内所给词的适当形式填空。1.IfI_________(know)moreaboutgivingfirstaid,I_______________(help)themwhentheaccidenthappened.2.IfI______(be)aman,I___________(run)forpresident.3.—Doyouthinkthethiefenteredthroughthesidedoor?—No,ifhe_______(have),he_____________________(notbr