高中情态动词用法详解

ItwaslastrevisedonJanuary2,2021高中情态动词用法详解情态动词一、情态动词的特点:1.没有人称和数的变化。2.有些情态动词有过去式的变化:.will→would,can→could,may→might,dare→dared二、情态动词的否定式:情态动词+not+动词原形cannot:can't,mustnot:mustn't,neednot:needn't三、情态动词的用法及相互区别,是考试的内容之一。1.can,beabletobeableto 表 关于同志近三年现实表现材料材料类招标技术评分表图表与交易pdf视力表打印pdf用图表说话 pdf 示经过努力后,能够做到;beableto有多种形式的变化。can1).表示体力或脑力方面的能力;2).表示允许、可能性。could是can的过去式,表示过去有能力及过去存在的可能性;用于疑问句表示委婉地提出问题。1)Thefirespreadthroughthehotelveryquicklybuteveryone____getout.A.hadtoB.wouldC.couldD.wasableto2)-Willyoustayforlunch-Sorry,__.Mybrotheriscomingtoseeme.A.Imustn'tB.Ican'tC.Ineedn'tD.Iwon't表示询问或说明一件事可不可做;表示某事有可能发生。might是may的过去式;用在疑问中比may委婉、客气。1)-MayItakethisbookoutofthereading-room?-No,youmustn't.(Yes,youmay.)2)-MightImakeasuggestion-Yes,youmay.3.must1).表示必须要做的事:必须2)表示很有把握的推断:一定,准是。have(has)to:have(has)gotto必须,不得不。过去式:hadto3)-MustIgettothestationbeforethreeo'clock?-Yes,youmust.(No,youneedn't.)4)I'mafraidyouwillhavetowaitawhile.5)Shemustbeintheclassroomnow.6)Mary____beinParis,Isawherintownonlyafewminutesago.A.mustn'tB.shouldn'tC.can'tD.maynot4.shall1)在疑问句中,用于第一、三人称表示说话人征求对方的意见或向对方请求。2)用于二、三人称,表示说话人给对方的命令、警告、允诺等概念。1)-ShallIplaceanorderwithyounow-No,youneedn’t.-Shallheturndowntheradioabit-Yes,please.(No,pleasedon't.)2)YoushallhavetheEnglishbookassoonasIfinishit.3)Everythingthatheownsshallbetakenawayfromhim.4)Yourbrotherseldomcomestoseeyou,____A.doesheB.doesn'theC.willheD.isn'the5)It'safineday.Let'sgofishing,____A.won'tweB.willweC.don'tweD.shallwe5.should应该;应当1)Youshouldlistentothedoctor'sadvice.2)Youshouldstudythearticlecarefully.6.will,would1)在疑问句中用于第二人称,表示说话人向对方提出请求或询问。用would语气更加婉转。2)will表示现在的习惯性动作或状态;would表示过去的习惯性动作或状态。3)will用于各种人称,表示意志、意愿、决心、允诺;would表示过去时间的意志、意愿、......。(1)Don'tsmokeinthemeetingroom,___youA.doyouB.willyouC.canyouD.couldyou-Willyoucomewithme-Yes,Iwill.(Iamsorry,Ican't.)(2)-Wouldyoutellussomethingaboutyourself-Yes,Iwill.(3)-It'smybirthdaytomorrow.Don'tforgettocometomyparty.-_____.A.Idon'tB.Iwon'tC.Ican'tD.Ihaven't7.oughtto应该;应当1)Yououghtn'ttosmoketoomuch.2)She____forwhatshehasdone.A.oughttopraise?B.oughtbepraisedC.oughttohavepraised?D.oughttobepraiseddaredaretocome2.darecome1)Hedarenottellthetruth.2)Hedoesn'tdaretocomeoutatnight.3)Idon'tknowwhetherhe____try.A.dareB.needsC.wantsD.isallowed9.need1).作为情态动词:必须2).作为实义动词:需要A.主语是人need(todosomething;tobedonebysomebody)B.主语是事物need(doing;tobedone)1)-Dotheyneedtotakeanybookswiththem?-No,theydon'tneedto.2)-Needwebuyanynewequipment-No,weneedn't.3)Thisfarmtoolneedsrepairing.Thisfarmtoolneedstoberepaired.4)-ShallItellJohnaboutit-No,you___.I'vetoldhimalready.A.needn'tB.wouldn'tC.mustn'tD.shouldn't5)It'safineday.You____takearaincoatwithyou.A.can'tB.mustn'tC.needn'tD.maynot情态动词+不定式的完成式是高考的考试要点1.can(could)+have+过去分词2.can't(couldn't)+have+过去分词3.must+have+过去分词4.may(might)+have+过去分词5.needn't+have+过去分词6.should(oughtto)+have+过去分词7.shouldn't(oughtn'tto)+have+过去分词1).Can(Could)theyhavecompletedtheirworksosoon2)Shecan't(couldn't)havemakeamistake.3)Sincetheditchisfullofwater,it____(rain)lastnight.4)Hesaidthatshemighthavemisunderstoodhim.1情态动词的语法特征　1）情态动词不能表示正在发生或已经发生的事情，只表示期待或估计某事的发生。　2）情态动词除ought和have外，后面只能接不带to的不定式。　3）情态动词没有人称，数的变化，即情态动词第三人称单数不加-s。　4）情态动词没有非谓语形式，即没有不定式，分词，等形式。2比较can和beableto1）can　could表示能力；可能(过去时用could),只用于现在式和过去式(could)。beableto可以用于各种时态。　Theywillbeabletotellyouthenewssoon.他很快就能告诉你消息了。2）只用beableto　a.位于助动词后。　b.情态动词后。　c.表示过去某时刻动作时。　d.用于句首表示条件。　e.表示成功地做了某事时，只能用was/wereableto，不能用could。　　　HewasabletofleeEuropebeforethewarbrokeout.　　=HemanagedtofleeEuropebeforethewarbrokeout.注意：could不表示时态1）提出委婉的请求，（注意在回答中不可用could）。　　---CouldIhavethetelevisionon?　　---Yes,youcan./No,youcan't.2）在否定，疑问句中表示推测或怀疑。　　　　Hecouldn'tbeabadman.　　　　　　他不大可能是坏人。3比较may和might1）表示允许或请求；表示没有把握的推测；may放在句首，表示祝愿。　　　　MayGodblessyou!　　　　Hemightbeathome.注意：might表示推测时，不表示时态。只是可能性比may小。2）成语：may/mightaswell，后面接不带to的不定式，意为"不妨"。　　　Ifthatisthecase,wemayaswelltry.典型例题　Peter___comewithustonight,butheisn'tverysureyet.　A.must　　B.may　C.can　D.will　答案B.表可能性只能用may.　此句意可从后半句推出。4比较haveto和must1)　两词都是'必须'的意思，haveto表示客观的需要，must表示说话人主观上的看法，既主观上的必要。　　Mybrotherwasveryill,soIhadtocallthedoctorinthemiddleofthenight.　我弟弟病得很厉害，我只得半夜里把医生请来。(客观上需要做这件事)　　Hesaidthattheymustworkhard.他说他们必须努力工作。（主观上要做这件事）2)　haveto有人称、数、时态的变化，而must只有一种形式。但must可用于间接引语中表示过去的必要或义务。Hehadtolookafterhissisteryesterday.3）在否定结构中：don'thaveto　表示"不必"　　　　　　　　　　mustn't　　　　表示"禁止"，　　Youdon'thavetotellhimaboutit.　你不一定要把此事告诉他。　　Youmustn'ttellhimaboutit.　　　　你一定不要把这件事告诉他。5must表示推测　1)must用在肯定句中表示较有把握的推测，意为"一定"。　2)must表对现在的状态或现在正发生的事情的推测时，must后面通常接系动词be的原形或行为动词的进行式。　　　Youhaveworkedhardallmustbetired.　你辛苦干一整天，一定累了。（对现在情况的推测判断）　　　Hemustbeworkinginhisoffice.他一定在办公室工作呢。　比较：　　　Hemustbestayingthere.　　　　他现在肯定呆在那里。　　　Hemuststaythere.　　　他必须呆在那。　3)must表示对已发生的事情的推测时，must要接完成式。　　Ididn'thearthephone.Imusthavebeenasleep.　我刚才没有听到电话，我想必是睡着了。　4)must表示对过去某时正发生的事情的推测，must后面要接不定式的完成进行式。　　---Whydidn'tyouanswermyphonecall?　　---Well,Imusthavebeensleeping,soIdidn'thearit.　5)否定推测用can't。　　IfTomdidn'tleavehereuntilfiveo'clock,hecan'tbehomeyet.　如果汤姆五点才离开这儿，他此时一定还未到家。6表示推测的用法　can,could,may,might,must皆可表示推测，其用法如下：1）情态动词+动词原形。　　表示对现在或将来的情况的推测，此时动词通常为系动词。　　Idon'tknowwheresheis,shemaybeinWuhan.2）情态动词+动词现在进行时。　　表示对现在或将来正在进行的情况进行推测。　　Atthismoment,ourteachermustbecorrectingourexampapers.　　这时，我们老师想必在批改试卷。3）情态动词+动词完成时。　　表示对过去情况的推测。　　WewouldhavefinishedthisworkbytheendofnextDecember.　　明年十二月底前我们很可能已完成这项工作了。　　Theroadiswet.Itmusthaverainedlastnight.　　地是湿的，昨天晚上一定下雨了。4）情态动词+动词的现在完成进行时。　　表示对过去正在发生事情的推测。　　Yourmothermusthavebeenlookingforyou.　　你妈妈一定一直在找你。5）推测的否定形式，疑问形式用can't,couldn't表示。　　Mikecan'thavefoundhiscar,forhecametoworkbybusthismorning.　　迈克一定还没有找回他的车，因为早上他是坐公共汽车来上班的。　注意：could,might表示推测时不表示时态，其推测的程度不如can,may。7情态动词+have+过去分词1)may(might)have+donesth,can(could)have+donesth　表示过去，推测过去时间里可能发生的事情。　　Philipmay(might)havebeenhurtseriouslyinthecaraccident.　　Philipcan(could)havebeenhurtseriouslyinthecaraccident.2)　musthave+donesth，对过去时间里可能发生的事情的推测，语气较强，具有"肯定"，"谅必"的意思。　---Lindahasgonetowork,butherbicycleisstillhere.　---Shemusthavegonebybus.3)oughttohavedonesth,shouldhavedonesth　　本应该做某事，而事实上并没有做。否定句表示"不该做某事而做了"。　　Yououghtto(should)havebeenmorecarefulinthisexperiment.　　Heoughtnottohavethrowntheoldclothesaway.（事实上已扔了。）　　oughtto在语气上比should要强。4)needn'thavedonesth　本没必要做某事　　Idressedverywarmlyforthetrip,butI　needn'thavedoneso.Theweatherwashot.5)wouldliketohavedonesth　本打算做某事　　　Iwouldliketohavereadthearticle,butIwasverybusythen.8should和oughtto　　should和oughtto都为"应该"的意思，可用于各种人称。　　---Oughthetogo?　　---Yes.Ithinkheoughtto.　　表示要求，命令时，语气由should（应该）、hadbetter最好）、must（必须）渐强。9hadbetter表示"最好"　　hadbetter相当于一个助动词，它只有一种形式，它后面要跟动词原形。　　hadbetterdosth　　hadbetternotdosth　　Itisprettycold.You'dbetterputonmycoat.　　She'dbetternotplaywiththedog.　　hadbetterhavedonesth表示与事实相反的结果，意为"本来最好"。　　Youhadbetterhavecomeearlier.10wouldrather表示"宁愿"　wouldratherdo　wouldrathernotdo　wouldrather…than…　宁愿……而不愿。　还有wouldsooner,hadrather,hadsooner都表示"宁愿"、"宁可"的意思。　IfIhaveachoice,Ihadsoonernotcontinuemystudiesatthisschool.　Iwouldratherstayherethangohome.=Iwouldstayhereratherthangohome.典型例题----Shallwegoskatingorstayathome?----Which___do?　　　　　A.doyourather　　B.wouldyourather　C.willyourather　D.shouldyourather答案B。本题考查情态动词rather的用法，wouldrather+dosth意为"宁愿"，本题为疑问句，would提前，所以选B。11will和would　注意：　1）wouldlike；Wouldliketodo=wantto想要，为固定搭配。　　Wouldyouliketogowithme?　2）Willyou…　Wouldyoulike…表示肯定含义的请求劝说时，疑问句中一般用some,而不是any。　　Wouldyoulikesomecake?　3）否定结构中用will，一般不用would,won'tyou是一种委婉语气。　　Won'tyousitdown12情态动词的回答方式　　问句　　　肯定回答　　　　否定回答Needyou…　　Yes,Imust.　　　No,Ineedn'tMustyou…　　　　　　　　　　　/don'thaveto.典型例题1）---CouldIborrowyourdictionary?　　---Yes,ofcourse,you____.　　A.might　B.will　C.can　D.should　答案表示委婉的语气，并不为时态。答语中ofcourse，表示肯定的语气，允许某人做某事时，用can和may来表达，不能用could或might。复习：will与you连用，用来提出要求或下命令。should与you连用，用来提出劝告。2）---ShallItellJohnaboutit?　　---No,you___.I'vetoldhimalready.　　　A.needn't　　B.wouldn't　　C.mustn't　　D.shouldn't　答案A。needn't不必，不用。wouldn't将不,不会的。mustn't禁止、不能。shouldn't　不应该。本题为不需要，不必的意思，应用needn't。3）---Don'tforgettocometomybirthdaypartytomorrow.　　---______.　　A.Idon't　B.　Iwon't　C.Ican't　D.Ihaven't　　答案B.　will既可当作情态动词，表请求、建议、也可作为实义动词表"意愿、意志、决心"，本题表示决心，选B。13带to的情态动词　带to的情态动词有四个：oughtto,haveto,usedto,beto,如加上havegotto,(=must),beableto，为六个。它们的疑问，否定形式应予以注意：　Dotheyhavetopaytheirbillbeforetheendofthemonth?　Shedidn'tusetoplaytennisbeforeshewasfourteen.　Yououghtnottohavetoldherallaboutit.　Oughthetoseeaheartspecialistatonce.　oughtto本身作为情态动词使用。其他的词作为实义动词使用，变疑问，否定时，须有do等助动词协助。典型例题　Tomoughtnotto___meyoursecret,buthemeantnoharm.　　told　　telling　D.havingtold　答案A。由于后句为过去时，告诉秘密的动作又发生在其前因，此地应用过去完成时，但它在情态动词oughtto后，所以用have。14比较need和dare　这两词既可做实义动词用，又可做情态动词用。作为情态动词，两者都只能用于疑问句，否定句和条件句。need作实义动词时后面的不定式必须带to，而dare作实义动词用时,后面的to时常可以被省略。1)实义动词：need　（需要,要求）　　　　　　　need+n./todosth2)情态动词：need，只用原形need后加do，否定形式为neednot。　　Needyougoyet　　Yes,Imust./No,Ineedn't.3)need的被动含义：need,want,require,worth（形容词）后面接doing也可以表示被动：　　　needdoing=needtobedone练习.情态动词1.Shepassedmeinthestreetwithoutspeaking,she____me.A.can'tsee?B.can'thaveseenC.shouldn'thaveseen?D.shouldn'tsee2.-Theywerealreadyfivepeopleinthecarbuttheymanagedtotakemeaswell.-It___acomfortablejourney.A.can'tbeB.shouldn'tbeC.mustn'thavebeen?D.couldn'thavebeen3.He____youmorehelpeventhoughhewasverybusy.A.mighthavegivenB.mightgiveC.mayhavegivenD.maygive4.Shequickenedherpaceinorderthatshe____withtheothers.A.maycatchup?B.mightcatchupC.couldhavecaughtup?D.mighthavecaughtup5.Therewasplentyoftime,she____.A.mustn'thavehurried?B.couldn'thavehurriedC.mustnothurry?D.needn'thavehurried6.Ididn'thearthephone,I____asleep.A.mustbeB.musthavebeenC.shouldbeD.shouldhavebeen7.Hewasagoodrunnersohe____escapefromthepolice.A.mightB.succeededC.wouldD.wasableto8.We____lastnight,butwewenttotheconcertinstead.A.musthavestudiedB.mightstudyC.shouldhavestudiedD.wouldstudy9.Theyoungmanhasmadesomuchnoisethathe____nothavebeenallowedtoattendtheconcert.A.couldB.mustC.wouldD.should10.Asolidergothimoutofdanger.He____hurt.A.maynotB.canhavegotC.mighthavegotD.mightget11.-CouldIuseyourpen-Yes,ofcourseyou____.A.mustB.couldC.canD.might12.Johnny,you___playwiththeknife,you__hurtyourself.A.won't;can'tB.mustn't;mayC.shouldn't;must?D.can't;shouldn't13.Sir,you___besittinginthiswaitingroom.Itisforthiswomanandchildrenonly.A.oughtn'ttoB.can'tC.won'tD.needn't14.I____tellherthetruth.A.cannothelpB.can'tbutC.maynothelpD.couldbut15.Ihaveneitheraraincoatnoranumbrella.That'swhyI____waituntiltherainstops.A.mustB.shouldC.oughttoD.haveto16.Atrafficaccidenthappenedyesterdayandadriver____.A.mayhurtB.maybehurtingC.mayhavebeenhurt?D.maybehurt17.Adograninfrontofmymother'scarandshe____stopveryquickly.A.oughttoB.hadbetterC.mustD.hadto18.-IstayedatahotelwhileinNewYork.-Oh,didyouYou____withBarbara.A.couldhavestayedB.couldstayC.wouldstayD.musthavestayed19.Theplantisdead.I___itmorewater.A.willgiveB.wouldhavegivenC.mustgive?D.shouldhavegiven20.Acomputer___thinkforitself;itmustbetoldwhattodo.A.can'tB.couldn'tC.maynotD.mightnot21.It'snearlyseveno'clock.Jack___behereatanymoment.A.mustB.needC.shouldD.can22.Tomoughtnotto___meyoursecret,buthemeantnoharm.A.havetoldB.tellC.betellingD.havingtold23.-Alice,youfeedthebirdtoday,____-ButIfedityesterday.A.doyouB.willyouC.didn'tyouD.don'tyou24.-DoyouthinkIcouldborrowyourdictionary-____.A.Yes,youmayborrow?B.Yes,youcouldC.Yes,helpyourself?D.Yes,goon25.Iwasreallyanxiousaboutyou.You____homewithoutaword.A.mustn'tleave?B.shouldn'thaveleftC.couldn'thaveleft?D.needn'tleaveKey:1-5BDABD6-10BDCDC11-15CBABD16-20CDADA21-25CAACB全国各省市高考试卷中的情态动词试题1A(全国卷I）24.There'snolighton--they______beathome.A.can'tB.mustn'tC.needn'tD.shouldn't2(全国卷2)10.Wehopethatasmanypeopleas-possible_______joinusforthepicnictomorrow.A.needB.mustC.shouldD.can3(北京卷)25.--What'sthename?--Khulaifi._______Ispellthatforyou?A.ShallB.WouldC.CanD.Might4(上海春)26.Youknowheisnotgoingtoletusleaveearlyifwe___gettheworkdone.A.can'tB.maynotC.shouldn'tD.mustn't5(天津卷)11.Wehaveprovedgreatadventurers,butwehavedonethegreatestmarchevermadeinthepasttenyears.A.needn'tB.maynotC.shouldn’tD.mustn't6(四川卷)32.---IsJackondutytoday?---It________behim.It'shisturntomorrow.A.mustn'tB.won'tC.can'tD.needn't7(江西卷)24．Theweatherturnedouttobefineyesterday．I_______thetroubletocarrymyumbrellawithme．A．shouldhavetakenB．couldhavetakenC．needn'thavetaken?D.mustn'thavetaken8(陕西卷)youworkedlateyesterday,you_________havecomethismorning.A.mayn'tB.can'tC.mustn'tD.needn't9(福建卷)itwerenotforthefactthatshe_______sing,Iwouldinvitehertotheparty.A.couldn'tB.shouldn'tC.can'tD.mightnot10(湖北卷)31.__________fired,yourhealthcareandotherbenefitswillnotbeimmediatelycutoff.A.WouldyoubeB.ShouldyoubeC.CouldyoubeD.Mightyoube11(湖南卷)aspectsofapilot'sjob________beboring,andpilotsoften_______workatinconvenienthours.A.can;havetoB.may;canC.haveto;mayD.oughtto;must12(江苏卷)21.---IthinkI'llgiveBobaring.---You_______.Youhaven'tbeenintouchwithhimforages.A.willB.mayC.havetoD.should13(广东卷)22.--Musthecometosignthispaperhimself?--Yes,he___.A.needB.mustC.mayD.will14(浙江卷)19.---CouldIhaveawordwithyou,mum?---Ohdear,ifyou________.A.canB.mustC.mayD.should15(山东卷)30.--MayIsmokehere--Ifyou____,chooseaseatinthesmokingsection.A.shouldB.couldC.mayD.mustKeys:1-10ADCABCCDCB11-15ADBBD高考英语陷阱题总结归纳——情态动词◆典型陷阱题 分析 定性数据统计分析pdf销售业绩分析模板建筑结构震害分析销售进度分析表京东商城竞争战略分析 ◆1.“Mikeisoftenabsentfromclass.”“Tellhimhe_____answerforitifhegoesonbehavinglikethat.”A.shallB.willC.wouldD.can【陷阱】几个干扰项均有可能误选。【分析】最佳答案选用作情态动词主要有以下两个用法：（1）用于疑问句中征求意见。如：ShallIhelpyou要不要我帮帮你？ShallIopenthewindow要我把窗子打开吗？（2）用于陈述句中表示允诺、告诫、警告、威胁、命令、规定、必然性等（可用于各类人称）。如：Youshallsufferforthis.你会为此事吃苦头的。（表威胁）Eachcompetitorshallwearanumber.每个参赛者要戴一个号码。（表规定）Youshallheareverythingassoonasyoucome.你一来就可听到所有情况了。（表允诺）请做以下试题（答案均选shall）：（1）“Ipromisethatshe_____getanicepresentonherbirthday.”“Willitbeagreatsurprisetoher”A.shouldB.mustC.wouldD.shall2.You_______paytoomuchattentiontoyourreadingskill,asitissoimportant.A.cannotB.shouldn’tC.mustn’tD.needn’t【陷阱】几个干扰项均有可能误选。【分析】最佳答案选…too…是英语中一个十分有用的表达，意为“不可能太……，无论怎样……也不算过分，越……越……”。如：Youcan’tbetoocareful.你越仔细越好。Youcan’tpraisethetoomuch.这本书值得大加赞扬。Wecannotworktoomuchforthepeople.我们为人民做工作是不可能做过头的。Awomancannothavetoomanyclothes.女人买的衣服再多也不算多。注：有时也可用cannever,impossible等与too连用来表示类似意思。如：Itisimpossibletogettheretoosoon.去那儿越早越好。3.“IsJohncomingbytrain”“Heshould,buthe_____not.Helikesdrivinghiscar.”A.mustB.canC.needD.may【陷阱】可能误选B或C.【分析】最佳答案为表推测，maynot意为“可能不（会坐火车来）”。句中的Heshould为Heshouldcomebytrain之省略，由于其后出现转折连词but，说明语意有变化，再结合下文的Helikesdrivinghiscar，便可决定此题选D.注意，不能选B，因为can表示推测时通常不用肯定陈述句。4.“Iheardtheywentskiinginthemountainslastwinter.”“It____truebecausetherewaslittlesnowthere.”A.maynotbeB.won’tbeC.couldn’tbeD.mustn’tbe【陷阱】几个干扰项均有可能误选。【分析】此题最佳答案为C，主要由下文的becausetherewaslittlesnowthere这一语境所决定，既然“没下什么雪”，那么“滑雪”就应是“不可能”，所以选couldn’tbe，即选C.5.“Doyouthinkheislazy”“I_____soonce,butIdon’tnow.”A.mayhavethoughtB.canhavethoughtC.maythinkD.mightthink答案选A.从答话人的语境可知，空格处的意思“曾经这样想过”，即对过去情况作推测，故应用“情态动词+动词完成式”；又因为can表推测不用于肯定句，故选A.请看类例：Theiranswersareexactlythesame—oneofthem______fromtheother.A.mustcopyB.musthavecopiedC.shouldcopyD.shouldhavecopied答案选B，既然两人的答案完全一样，说明“抄袭”已经发生，故用“情态动词+动词完成式”，根据句意，应选B而不能选D.6.You_____beright,butIdon’tthinkyouare.A.canB.couldC.mustD.should【陷阱】几个干扰项均有可能误选。【分析】从语境上看，C、D不宜选，在剩下的A和B中，许多同学想当然地选了A，认为整个句子为现在时态，所以选can，而不选过去式could，但是最佳答案却是B而不是A.按照英语语法，情态动词can用于推测表示可能性时，通常只用于否定句或疑问句中，而不用于肯定句中；但could用于表推测时，却不仅可用于否定句和疑问句，也可用于肯定句，且此时的could并不是can的过去式，与can也没有时间上的差别，只是could比can语气更委婉，所以答案选B.注：can在以下特殊情况下，也可用于肯定句。一是表示抽象的可能性，即从理论上或逻辑上分析是可能的，但是实际上未必会发生。如：Anyonecanmakemistakes.任何人都可能会犯错误。二是后接“be（get,seem,become）＋形容词”，表示“有时会”、“时常会”等。如：Myfathercanbeveryunreasonable.我父亲有时候很不讲道理。◆精编陷阱题训练◆1.“Ithoughtyouwouldn’tmind.”“Well,asamatteroffactIdon’t,butyou_____mefirst.”A.shouldaskB.shouldhaveaskedC.mustaskD.musthaveasked2.“Icalledyouyesterday.Awomananswered,butIdidn’trecognizehervoice.”“Oh,it_____myauntJean.”A.mustbeB.musthavebeenC.mightbeD.canhavebeen3.Thatcarnearlyhitme;I______.A.mightbekilledB.mighthavebeenkilledC.maybekilledD.maybeenkilled4.It’saverykindoffer,butIreally_____acceptit.A.mustn’tB.needn’tC.can’tD.don’t5.Thepolicestillhaven’tfoundher,butthey’redoingallthey_____.A.mayB.canC.mustD.will6.You_____practisethedrumswhilethebabyissleeping.A.needn’tB.mightn’tC.mustn’tD.won’t7.You_____himthenews;heknewitalready.A.needn’ttellB.needn’thavetoldC.mightn’ttellD.mightn’thavetold8.Asshe’snothere,Isupposeshe_____home.A.mustgoB.musthavegoneC.mightgoD.mightbegoing9.AreyoustillhereYou______homehoursago.A.shouldgoB.shouldhavegoneC.mightgoD.mayhavegone10.“Icalledyouyesterday.Awomananswered,butIdidn’trecognizehervoice.”“Oh,it_____myauntJean.”A.mustbeB.musthavebeenC.mightbeD.canhavebeen11.I_______havemethimalongtimeago.Bothhisnameandfaceareveryfamiliar.A.mayB.canC.wouldD.should13.“Shallwegoshopping”“Sorry,we_______buyanythingnowbecausenoneoftheshopsareopen.”A.mustn’t　　B.needn’tC.can’tD.shouldn’t14.Theyoftengototherestaurantsformeals.They_____beverypoor.A.mustn’tB.can’tC.maynotD.needn’t15.Ididn’tseeherinthemeetingroomthismorning.She______havespokenatthemeeting.A.mustn’tB.shouldn’tC.needn’tD.couldn’t17.He______thetestagain,inwhichcase,hismotherwillbeverydisappointed.A.mightfailB.musthavefailedC.shouldfailD.couldhavefailed18.“Whydidn’tshecometothemeetingyesterday”“I’mnotsosure.She______ill.”A.shouldbeB.shouldhavebeenC.mustbeD.mighthavebeen19.WhydidyoujustsitandwatchYou_______me.A.couldhelpB.shouldhelpC.couldhavehelpedD.musthavehelped20.“You______yourteacherforhelp.Heiskind-hearted.”“Yes.Awholeday_______.”A.canask,willwasteB.musthaveasked,hadwastedC.couldhaveasked,waswastedD.shouldn’thaveasked,wouldbewasted21.“IsthereaflighttoLondonthisevening”“There_______be.I’llphonetheairportandfinditout.”A.mustB.mightC.wouldD.can22.“Showmeyourpermit,please.”“Oh,it’snotinmypocket.It______.”A.mightfalloutB.couldfalloutC.shouldhavefallenoutD.musthavefallenout23.“Lookatthesetracks.It_______beawolf.”“Don’tbesosure.Ithinkit_______beafox.”A.must;couldB.may;mightC.need;mustD.could;need25.“DidJimcome”“Idon’tknow.He_______whileIwasout.”A.mighthavecomeB.mightcomeC.mushhavecomeD.shouldhavecome◆答案与解析◆1.选B，should后接动词完成式表示“本来应该做某事，结果未做”，此处含有责备之意。2.选B，对过去情况的肯定推测，宜用“情态动词+动词完成式”，再根据句意，可确定答案为B.注：can表示推测通常不用于肯定陈述句。3.选B，表示过去可能发生而实际上未发生的事，用might+动词完成式。若只是推测过去可能已经发生的事，则可用may[might]+动词完成式，如Hemay[might]havegone.他可能已经走了。4.选C.由句意可知。5.选B，doallonecan意为“尽力”或“竭尽全力”。6.选C，mustn’t在此相当于can’t，且语气更强。7.选B，“needn’t+动词完成式”的意思是：本来不必做某事，但实际上做了。上句意思是“你本来不必告诉他这个消息的，因为他（当时）已经知道了”。注意，句中knew为过去式。8.选B，must后接动词完成式表示对过去情况的肯定推测，意为“一定已经做了某事”。9.选B，should后接动词完成式表示“本来应该做某事，结果未做”。10.选B，对过去情况的肯定推测，宜用“情态动词+动词完成式”，再根据句意，可确定答案为B.注：can表示推测通常不用于肯定句。12.选havedonesth表示对过去可能发生的事进行推测，意为“可能曾经”。13.选C.根据上下文的语境推知。can’t意为“不能”。14.选B.根据上下文的语境推知。can’t表推测，意为“不不能”。16.选’thavedonesth表示对过去情况进行推测，意为“过去不可能发生过某情况”。17.选A.根据下文的willbe可知，“他考试再不及格”是将来的事，据此可排除B和D.再根据语意，排除C.18.选D.从时间上看，由于是昨天没来开会，所以推测他生病也应指昨天，故排除A和C.从语境上看，既然上文说I’mnotsosure，那么说明说话者对自己的推测没有很大把握，故选D.19.选C.根据上文的过去时态可知，此句谈的是过去的事，故排除A和C.根据语境排除D.20.选’thavedonesth结构在此表示责备，指过去本来可以做某事但实际上未做。第二空填waswasted，陈述的是过去的一事实。21.选B.根据下文的I’llphonetheairportandfinditout可知，说话人对自己的推测没有很大把握，故选might.若选A，语气太强，不合语境；若选D，不合语法习惯，因为can表推测通常不用于肯定陈述句中。22.选D.既然“通行证现在不在口袋里”，那么它“掉出去”应发生在过去，故排除A和B.比较选项C和D所表示的意思，选D更恰当。24.选A.根据Don’tbesosure可知前面一空应填must.第二空填的could表示推测，虽为过去式形式，但表示现在意义，语气较委婉，它与表推测的can主要用于否定句和疑问句不同，它可以用于肯定陈述句。25.选A.根据句中有关时态可知“他来”发生在过去，故排除B；根据Idon’tknow可知选项C语气太肯定，不合适；选项D的意思是“本来应该来”，与语境不合。