2人教版必修三unit2情态动词.pptx

主要情态动词主要情态动词vCan,couldvMay,mightvWill,wouldvShall,shouldvMustvHavetovOughttovNeedvdare观察情态动词的特性1.I can speak English.2.He can not go to the party.3.You should go to a doctor tomorrow.4.I can speak English now,but when I was 5 years old,I couldnt.1.有词义；2.后跟动原；3.没有人称和数的变化；4.部分情态动词有时态的变化；5.不单独做谓语Modalverbs2oughtto表示表示“应该应该”oughtto的否定式为的否定式为oughtntto或或oughtnotto(1)常指常指客观的义务或责任客观的义务或责任.大多数情况下可用大多数情况下可用should代替，但比代替，但比should语气重语气重。Weoughttostoppollutingnature.你应该戒烟。你应该戒烟。Yououghttoquitsmoking.外国人不应该加入这场内战。外国人不应该加入这场内战。Foreignersoughtnottotakepartinthecivilwar.b.表示劝告、建议。表示劝告、建议。此时此时should和和oughtto可通用可通用，但在，但在疑疑问句中常用问句中常用should。Youshould/oughttogotoclassrightaway.我们应该打开窗户。我们应该打开窗户。ShouldIopenthewindow?我们接下来应该做什么？我们接下来应该做什么？Whatshouldwedonext?YououghttohelphimwithhisEnglish,_?A.wontyouB.oughtnotyouC.shouldntyouD.wouldntyouc.oughtto可表示推测，意为可表示推测，意为“按道按道理应该理应该”。（与。（与should用法相同）用法相同）Trytotranslate:Heoughtto/shouldbehomebynow.Heworksveryhard,heoughttogetgoodgradesintheexam.Canyougiveadvice?做一些运动做一些运动Yououghtto/shoulddosomesports.Asastudent,yououghttohandinthehomeworkontime.按时交作业按时交作业haveto的用法的用法1)haveto意思是意思是“不得不，必须不得不，必须”。如：如：今天下午我不得不参加一个重要今天下午我不得不参加一个重要的会议。的会议。Ihavetoattendanimportantmeetingthisafternoon.2)haveto的否定形式是的否定形式是donthaveto,意为意为“不必不必”。表示没有义务或者没有必要做某事。表示没有义务或者没有必要做某事。如：他们现在没有必要买电脑。如：他们现在没有必要买电脑。Theydonthavetobuyacomputernow.区分：区分：must表示一种主观的需要，而表示一种主观的需要，而haveto表示一种客观的需要表示一种客观的需要（1）Motherisout,soIlookaftertheshop.（2）Iwanttoenteratopuniversity,soIstudyveryhard.【考例考例】Thebosshasgiveneveryoneaspecialholiday,sowe_gotoworktomorrow.(上海上海2007春春)A.cantB.mustntC.donthavetoD.shouldnt【点拨点拨】考查情态动词。根据题意考查情态动词。根据题意,可知可知这里表示这里表示“没有必要没有必要”,故只能选故只能选C项。项。【考例考例】Whatdoyouthinkwecandoforouragedparents?You_doanythingexcepttobewiththemandbeyourself.(重庆重庆2007)A.donthavetoB.oughtnttoC.mustntD.cant【点拨点拨】根据题意根据题意“除了和他们呆在一除了和他们呆在一起做你自己外起做你自己外,没有必要做任何事情。没有必要做任何事情。”可知这里选择可知这里选择donthaveto表示表示“不必不必”。故选。故选A项。项。3.need(情态动词情态动词/实义动词）实义动词）(1)need作情态动词时作情态动词时,意为意为“需要，有必要需要，有必要”后跟动词原形，多用于疑后跟动词原形，多用于疑问句问句,否定句或条件句中。否定句或条件句中。Youneedntgotoworktoday.NeedIfinishtheworktoday?Yes,youmust/haveto./No,youneednt.(2)need还可做实义动词，后跟to do 动词不定式.和其他实义动词一样，可用于各种句式，有时态，人称和数的变化，构成否定和疑问句时要借助于助动词do.You need to be careful.否定句You dont need to be careful.他需要休息一下。He needs to have a rest.Translation我的房间需要打扫。My room needs to be cleaned.need作“需要”讲时，其后跟不定式的被动形式相当于跟v-ing的主动形式。want 与require做需要讲时，也有这种用法。=My room needs cleaning.我的自行车需要修理。My bike needs to be repaired.=My bike needs repairing.注意对注意对need问句的回答问句的回答:-NeedIfinishtheworktoday?-Yes,_.No,_.No,_.youmust/havetoyouneedntyoudonthavetoneednt对其它情态动词的回答对其它情态动词的回答:-ShallItellJohnaboutit?-No,you_.-No,you_.-Mustwedoitnow?-No,you_.-No,you_.needntdonthavetoneedntdonthaveto4.dare的用法a.dare既可作情态动词也可做实义动词。做情态动词时多用于疑问句，否定句，条件状语从句以及表示怀疑的名词性从句中，意为“敢。”。I dare not/darent walk through the forest at night.变为一般疑问句：b.dare 做实义动词时，后跟to do 动词不定式，在否定句中不定式符号to也可以省略。和其他实义动词一样，可用于各种句式，有时态，人称和数的变化。He dared to jump over the stream.He will dare to face any danger.I have never dared(to)go back to take a look.He doesnt dare(to)walk at night.表示否定的情态动词的用法表示否定的情态动词的用法:mustntneednt=(donthaveto)cantmaynotshouldnt(=oughtnotto)部分情态动词的否定式是情态动词中的部分情态动词的否定式是情态动词中的考点之一。考点之一。（一）表对过去发生的事情的推测（一）表对过去发生的事情的推测may/mighthavedone可能已做可能已做musthavedone一定已做（肯定句中）一定已做（肯定句中）canthavedone（过去）不可能做了。（过去）不可能做了。-Whereismypen?-Imusthavelostit.Thelightinhisroomisstillon,sohecanthavegonetobed.Ourheadmastermighthaveknownwhatyoudidyesterday.情态动词情态动词+havedone结构的用法结构的用法(二二)couldhavedone指指“本来能做而实际未做本来能做而实际未做”或或“可能已经做过某事可能已经做过某事”，表达遗憾的感情色彩，表达遗憾的感情色彩 Youcouldatleasthavesent(邮寄邮寄)fivecards.（三）（三）needhavedone表示本来需要做某事而实际未做表示本来需要做某事而实际未做”neednthavedone表示过去本来没有必要做表示过去本来没有必要做某事，某事，但事实上却做了。但事实上却做了。Therewasplentyoftime.Sheneednthavehurried.（四）四）should/oughttohavedone本来应做而未做，表达遗憾、责备等感情色彩本来应做而未做，表达遗憾、责备等感情色彩Youshould/oughttohavemadethedecisionaweekago.Ishouldnthavemadesuchafoolishmistake.ItoldSallyhowtogetthere,butperhapsIshouldhavewrittenitoutforher.Iwasreallyanxiousaboutyou,youshouldnthavelefthomewithoutaword.1.Ithoughtyou_likesomethingtoread,soIhavebroughtyousomebooks.A.canB.mightC.willD.must2.Icantfindmypeneverywhere.I_it.A.mightloseB.wouldhavelostC.shouldhavelostD.musthavelost高考链接高考链接3.Ididnthearthephone.I_asleep.A.mustbeB.musthavebeenC.shouldbeD.shouldhavebeen4.-Iheardtheywentskiinginthemountainslastwinter.-It_truebecausetherewaslittlesnowthere.(2002北京北京高考题高考题)A.maynotbeB.wontbeC.couldntbeD.mustntbe5.Itsnearlysevenoclock.Jack_beherenow.A.willB.needC.shouldD.can6.-CouldIborrowyourdictionary?Yes,ofcourseyou_.A.mightB.willC.canD.should7._youmindmysmokinghere?A.ShouldBCouldC.MightD.Would8.-IsJohncomingbytrain?-Heshould,buthe_not.Helikesdrivinghiscar.(2002高考题）高考题）A.mustB.canC.needD.may9.Ithasbeenannouncedthatcandidates(应试者，考生应试者，考生)_remainintheirseatsuntilallthepapershavebeencollected.(2002上海上海高考题）高考题）A.canB.willC.mayD.shall1Childrenunder12yearsinthatcountry_beunderadultsupervisionwheninapubliclibrary.(2007上海）上海）A.mustB.mayC.canD.need 2DoyouknowwhereDavidis?Icouldntfindhimanywhere.(2005湖北湖北)Well.He_havegonefarhiscoatsstillhere.AshouldntBmustntC.cantDwouldnt 3.Theweatherturnedouttobefineyesterday.I_thetroubletocarrymyumbrellawithme.(2006江西）江西）AshouldhavetakenBcouldhavetakenCneednthavetakenDmustnthavetaken4Musthecometosignthispaperhimself?Yes,he.(2006广东广东)A.needB.mustC.mayD.will5.Thereslightonthey_beathome.(2006全国全国I)A.cantB.mustC.mightD.shall6.Youcantimaginethatawell-behavedgentleman_besorudetoalady.2001上海上海)A.mightB.needC.shouldD.wouldDeal with the following situations using as many modal verbs as you can.Give your advice:vYour little sister asks you how to keep fit.-should,have to,neednt,ought to,had bettervLi Ming says he has finished his homework,but he cant find it now.-can,must,may,may/might have,must have.,cant/couldnt have.vAn old lady just dropped ten yuan as she got off the bus.If you get off to give it to her,you will probably be late for school.-should,could,might,wouldCan/couldv (自身具备的）能力v （be able to经过努力后）许可,请求 可能性,猜测（否定句不可能cant 疑问句可能吗）v May/might 可能性（常用语肯定句）许可 祝愿 vWill/would 请求/建议（would更委婉）意志/愿望/决心（would表过去）习惯性动作（总是，习惯于would表过去）用于否定句，表“不肯，不乐意”v shall （第一三人称疑问句）征求意见/请示（第二三人称陈述句）命令警告允诺Should（表劝告，建议）应该（表预测，可能性）应该会（表说话人惊讶，意外）竟然；到底 vMust 必须，应该（主观意愿）mustnt表不准，禁止表示肯定猜测（只用于肯定句中）意为“一定，准是”表示感情色彩，常指令人不快的事情，意为“偏偏，偏要”