高中英语情态动词课件精品.ppt

Grammar,情态动词用法,情态动词的语法特征,1）情态动词不能单独做谓语，除ought和have外，后面只能接不带to的不定式。,2）情态动词没有人称，数的变化，但有些情态动词，如can、will也有一般式和过去式的变化。,3）情态动词的“时态”形式并不是时间区别的主要标志，不少情况下，情态动词的现在式形式和过去式形式都可用来表示现在时间、过去时间和将来时间。,1.can1)表能力can表能力时意味着凭体力或脑力或技术等可以无甚阻力地去做某事。Icanclimbthispole.Heisonlyfour,buthecanread.Firecantdestroygold.,can和could：,2)表推测、可能性用于否定与疑问结构中Canthenewsbetrue?Itcantbetrue.Whatcanhepossiblymean?他可能是什么意思?can用在肯定句中表示理论上的可能性(一时的可能)。AhouseinthecenterofLondoncancostalotofmoney.Attendingtheballcanbeveryexciting.Theroadcanbeblocked.,3)表示请求或允许(和may意思相近)常见于口语。Can(May)Icomein?我能进来吗?CanIsmokehere?我可以在这里抽烟吗?,2)could的主要用法是：A.could是can的过去式,表示与过去有关的能力和推测:eg.Weallknewthattheyoungmancouldntbeadoctor.B.could可以代替can表示请求、“允许”。可表示委婉客气的提出问题或陈述看法,Couldyoulendmeyourdictionary?CouldIuseyourbike?Yes,youcan.ImafraidIcouldntgiveyouananswertoday.,Can与beabletodo的区别,时态：can只有现在时和过去(could),beabletodo有多种时态。（在将来时，完成时以及非谓语动词中应该用beabletodo.）,e.g.Sofar,doctorshavebeenabletodoverylittletotreat(治疗)thiskindofdisease(疾病).,Can表示一贯的能力，beableto表示客观能力和通过努力可以达到的能力1.Icantswim.ButIamsureIwillbeabletoswimthroughmorepracticing.2.Thefirespreadthroughthehotel,buteveryonewasabletogetout3.Whentheboatsankhewasabletoswimtothebank,YoucantbetoocarefulShecouldntbutagreetomyidea.Thegirlcouldnthelpcrying.Icantthankyouenough.Thefilmcouldntbeanyworse.Iburstoutlaughing;Icouldnthelpit,Can或could的否定形式构成习惯短语Cant.too.Cant.enough.无论怎样。也不过分。Cant(help)butdo不得不做，只好做Canthelpdoing情不自禁Canthelpit没有办法Cant.+比较级再。不过了（表示最高级）,may和might：may常用来表示：A.表示请求、允许;比can较为正式MayIcomein?Youmaygonow.(给予许可）B.表示说话人的猜测:“也许”“可能”:通常只用于肯定句和否定句中。,eg.-IbelievethemanisfromEngland.-ButImaybewrong.Theguestmayarrivethisafternoon.,在疑问句中，表示可能性用can。如：Wherecanhebe?他会在哪呢？,C.表示祝愿;但语气较正式:eg.Mayyousucceed!Mayyouhaveagoodjourney!might的用法有:多在间接引语中表示过去的可能和允许。如:Shesaidthathemighttakeherbike.她说他可以拿她的自行车去用,表示现在的许可,语气比may较委婉,一般用于疑问句(包括间接疑问句),不可用于肯定句或者否定句。如:MightIhaveawordwithyou?我可以和你说句话吗？,YoumaywellberightThereisnothingtodo,soImayaswellgotobed.Thefilmissoboring,andwemightaswellnothavecometoseeit.Maywell很可能、有充分的理由可以May/mightaswell最好，不妨Mightaswellhavedone还不如May.do/be.祝愿,当回答由may引起的问题时，否定答语要用mustnot,表示“不许可”、“不应该”、“不行”。MayIcomein?Yes,youmay.No,youcantNo,youmaynot.No,youmustntNo,youdbetternot.,will和would：,1.will是助动词或是情态动词？will用于构成将来时是助动词。用于表示“意志”“决心”“请求”是情态动词。would亦同理。eg.Iwilltellyousomethingimportant.我要告诉你一些重要的事。（助动词）,WillyoutellherthatImhere?请您告诉她说我在这儿，好吗？（情态动词）,Ifyougivehimtime,Tomwilltalkandtalkforhours.EverySaturdayeveningtheywillplaychesstogetherThedoorwontopenIlldomybesttohelpyou.Willyoupleasegivemeamessagewhenyouseehim?-Writetomewhenyougethome.-Iwill,经常性习惯性“老是、总是、终归是,表示功能，译作“能”或“行”,意愿,2人称，询问对方意愿或向对方提出请求,回答祈使句,Would表示有礼貌的请求或邀请（2人称）Wouldyouhelpus,please?请您帮助我们，好吗？WhenIhadsometrouble,hewouldencourageme.Wealltriedtoatophimsmokinginbedbuthewouldntlisten.,过去的习惯,意愿“要；愿”,Would与Usedtodo区别“过去常常”,Would-过去习惯的动作（现在有可能还有此习惯）Usedtodo-过去习惯的动作及状态（现在已经没有此习惯）,e.g.Hewouldgetupat8a.m.(现在有可能还在坚持此习惯)e.g.Heusedtogetupat8a.m.（现在已经不再坚持此习惯）,动作,e.g.ThereusedtobeanoldbuildingherewhenIwasyoung.,状态,shall和should：,1.shall用于构成将来时是助动词。shall用于征求对方的意见，表示“决心”是情态动词。eg:PerhapsIshallpayavisittoEnglandthiswinter.可能今年冬天我会去英国观光。（构成一般将来时,助动词）,Shallwegobytrain,Mom?妈妈，我们乘火车去好吗？（用于征求对方的意见，情态动词）Ishallgoatonce.我必须立即去。（表“决心”，情态动词）,1)用于第一、三人称征求对方的意见，WhatshallIwearonthejourney?Shallwedance?2)shall用于第二、三人称时表允诺，警告，命令，威胁。“必须，应该可以”Ifhepassestheexamination,heshallhaveaholiday.Youshallhaveitbacktomorrow.,3）用于第二、三人称用于法律法规条例等文件中的要求。“应该、必须”Itsrequiredinourregulationthatstudentsshallgotoschoolontime.Personsunder18shantbeemployedinnightwork.,2.should表示义务、建议、劝告等，意为“应该”。(oughtto)Studentsshouldrespectteachers.Theboysshouldntbeplayingfootball;theyshouldbeatschool.Its4:30,TheyshouldbeinNewYorkbynow.Heoughttosucceed,asheissodiligent.Itisstrangethatitshouldbesohottoday.Idontunderstandwhysheshouldhavemadesuchamistake.Shoulditraintomorrow,themeetingwillbepostponed.,劝告、建议,义务、责任,常规、常理的推测（正常情况下）按理应该,居然，竟然,与疑问词连用，表示意外、纳闷、惊讶等“究竟是，到底”,用于条件句中“万一”,must和haveto,1.must用于一般问句中,肯定回答用must否定式用neednt或donthaveto，做“不必”,mustnt表示“禁止，不允许”,MustIfinishallassignmentsatatime?,Yes,youmust.No,youneednt.,IdontlikethisTVset.Wemustbuyanewone.Therewasnomorebus.Theyhadtowalkhome.,2.表示“必须”这个意思时，must和haveto稍有区别。must着重说明主观看法，haveto强调客观需要。另外，haveto能用于更多时态。,Youmustbethenewteacher.Hemustbejoking.Thereisnobodyhere.Theymusthaveallgonehome.,3.must表示对某人某事的猜测，作“准是”，“一定”，一般用于肯定句中。对过去发生的事情作肯定判断用musthavedone,Hemustcomeandworryherwithquestion,justwhenshewasbusycookingthedinner.Ofcourse，afterIgavehermyadvice，shemustgoanddotheopposite.Howoldareyou,madam?Ifyoumustknow,Imtwicemysonsage.,4.must表示“偏要，硬要”，指做令人不快的事情,need与dare,实义动词,情态动词,实义动词vs情态动词,肯定句,实,情,e.g.Sheneedstostayathometoday.e.g.Hedarestojumpfromthehighwall.,e.g.Sheneedstayathometoday.e.g.Hedarejumpfromthehighwall.,疑问句,e.g.Doessheneedtostayathometoday?e.g.Doeshedaretojumpfromthehighwall?,e.g.Needshestayathometoday?e.g.Darehejumpfromthehighwall?,实,情,否定句,Dare作为实意动词的时候，否定句中的to可以省略,e.g.Hedoesntdare(to)jumpfromthehighwall.,实,e.g.Shedoesntneedtostayathometoday.e.g.Hedoesntdaretojumpfromthehighwall,情,e.g.Sheneedntstayathometoday.e.g.Hedarenotjumpfromthehighwall.,1.Itmusthaverainedlastnight,forthestreetsarewet.2.Itis8oclock.theymayhavearrived3.Helooksveryhappy.Hemightnothaveknowntheresult4.Hecouldnothavedonesuchathing.5.Shedidntcometoschoolyesterday.Canshehavebeenill?6.Theylefthereearlyandshouldhavearrivedbynow,情态动词表推测对过去情况的推测,7.youmighthavewrittentheletterwithoutmyremindingyouofit.8.Thedoctorcouldhaveavoidedtheaccident9.youshouldhavefinishedthetaskyesterday.10Iwasreallyanxiousaboutyou.youshouldnthavelefthomewithoutaword11.Heoughtnottohavetoldmeyoursecret,buthemeantnoharm,过去本可能（不用may),过去本能够却没有,过去本应该却没有,过去本不该,过去本不该,Itwasnotcoldyesterday.IneednthavetakenthethicksweatersoutItwasnotcoldyesterday.Ididntneedtotakethethicksweatersout,过去本不必,却做了.,过去不必做,实际也没有做,表推测的情态动词句子的反意疑问句Hemust/maybeintheroom,isnthe?Hecantbeintheroom,ishe?Hemusthavefinishedthework,hasnthe?Hemayhavedonetheworklastnight,didnthe?Hemusthavebeencaughtintheheavyrainlastnight,_,wasnthe,-_Igoouttoplay,mum?-No,you_.Youshoulddoyourhomeworkfirst.A.Might;wouldntB.May;hadbetternotC.Must;mustntD.Need;mustnt,B,Practice,2.-WhereisEmma?-Icantsayforsurewheresheis,butshe_beoutshopping.A.canB.shouldC.mustD.may,D,3.Theroomisinaterriblemess;it_cleaned.A.canthavebeenB.couldntbeC.mayhavebeenD.wouldbe,A,4.How_yousaythatyoureallyunderstandthewholestoryifyouhavecoveredonlypartofthearticle?A.canB.mustC.needD.may,A,5.There_beanydifficultyaboutpassingtheroadtestsinceyouhavepractisedalotinthedrivingschool.A.mustntB.shantC.shouldntD.neednt,C,6.-Therewerealreadyfivepeopleinthecarbuttheymanagedtotakemeaswell.-It_acomfortablejourney.()A.cantbeB.mustnthavebeenC.shouldntbeD.couldnthavebeen,D,7.Thefirespreadthroughthehotelveryquicklybuteveryone_getout.()A.hadtoB.wouldC.couldD.wasableto,D,8.Peter_comewithustonight,butheisntverysure.mustB.canC.mayD.will,C,9.-CouldIcallyoubyyourfir