高中英语语法情态动词 14页

情态动词I情态动词的特征：1.本身有词义。2.不能独立作谓语。2.后接动词原形一起构成谓语。3.不随人称和数的变化。II情态动词各自的基本意义及用法:1・can与could用法对比点cancould1、表“能力"Canyouliftthisheavybox?IcouldrTtunderstandwhathesaidatall.2、表“许可”Youcanuseadifferentmaterialinstead.HesaidIcouldborrowhisbike.3、“怀疑”No,no,itcaiftbetrue.Whatonearthcanthismean?Wethoughtthestorycouldnotbetrue.Howcouldyoubesocareless?4^can与beableto区别1.could代替can,表示语气更为婉转。Eg.CouldIuseyourbike?Yes,Ican2.can（能够）=beableto（仅表能力时）,但beableto表示一番努力后,才能做得到，且有更多的时态。2.may与might用法对比点maymight1.表“询问"MayI...?（=CanI...?）MightI…?（二CouldI...?）（但比用may更客气）2表吮许”Youmaytaketheboythere.Hetoldmehemightcome,（might与told相呼应）3.表呵能皿或许"Shemaynorlikethisplace.Fmafraidhemightnotlikethisplay.注：1.Mayl...?的答语。2.may可表示期望或祝愿Mayyousucceed!3.may（might）用于目的状语从句。肯定:Yes,youmay.否定：No,youmustn"t不行（语气强硕）No,youmaynot或No,you，dbetternotTheemperorgavethemsomegoldinorderthattheymightbegintheirworkatonce.3.must与haveto用法对比点musthaveto1.表“必须"（主观看法）必须；没有过去式，可用于间接引语屮。HetoldmeImustdoaccordingtowhathesaid・（客观需要）不得不，有多种时态。It，srainingheavily,wecan"tgonow. 2.疑问句MustI•••?Yes,youmust.（一定）No,youneedn^t./youdon5thaveto.Doyouhavetogotoday?Yes,wedo.Youdon"thavetoworryaboutthat.1 （不必）4.need与dare用法对比点needdare1•情态V.+动词原形1）否定式2）疑问式Heneednot(needn^t)go.…Needwedoitagain?…No,youneedn^tdoitagain.Hedarenotsayso.Dareshegooutaloneatnight?HowdareyousayFmunfair?Ifhedaredothat,he"llbepunished.Idaresay.(固定用法)2•实义v.+todo1）肯定式2）否定式3）疑问式Heneedstogo.Hedoesn^t(doesnot)needtogo.Doesheneedtodoitagain?No,hedoesn^tneedotdoitagain.Hedarestosay.Hedoesnot(doesn"t)daretosay.Ifyoudaretojumpintothewaterfromhere,sodareI.3.didnotneedtodo表示过去没必要做ShedidrTtneedtoattendthemeetingyesterday,andshestayedwithherchildren^她没有参加)5-should与oughtto用法对比点shouldoughtto1、表“应该”表劝告、建议Youshouldlistentothedoctor^advice.WeshouldlearnfromZhangHua.“有责任有必要F故某事Yououghttofinishyourworkbeforeyougohome.Weoughttohelpeachother.2、表“估计"Theyshouldgethomebynow.“非常可能"的事，可译为“总应该"Ifwestarttoworkrightnow,weoughttofinishitbeforelunch.注：1)should还可在虚拟语气中的使用2)注意：oughtto的疑问式及否定式---Oughthetogo?---Yes,Ithinkheoughtto.・・・No,heoughtn"tto.否定式：oughtn^todo(不说oughttonotdo)反疑问句：oughtn"t•6.shall与will用法shallwill1.征询对方意见或请求指示，用于第一、三人称：ShallI(we)...?Shallhe(she)...?WhereshallI(we)waitforyou?1•询问对方的意思或向对方提出要求：Willyou(please)...?Won"tyou...?Wouldyouliketo...?(would替代will更客气)Won"tyougoandseethefilm?你不去看电影吗…Yes,IthinkIwill.不，我想去。2.表示说话人的“意愿"有“命令杠警告T虽制^允诺^决心"等，用于第二、三人称。YoushalldowhatItellyou（todo）.我叫你干什么你就干H么。Everythingshallbedonetosavetheship.一定要竭尽全力来拯救这艘船。2.表示“意志"“意愿”，用于各种人称：Iwon"tdoanythingyoudon^tlike.我不会做任何你不喜欢的事。Would表示过去时间的“意志”“意愿”Shylockwouldnottakethemoneyearlier.夏洛克先前是不肯要钱的。 7.usedto与would用法usedtowould1•表示过去的动作、状态，重在与现在情况的对比，不一定要有时间状语。Iusedtoplaycardsalot,butnowIseldomplay.Myhometownisnotwhatitusedtobe.1•只表示过去动作的重复，有明确的时间状语。IwouldgotoseemygrandfatheronSundaywhenhewasinthemiddleschool.2.would后只接表动作的动词，不接表认识或状态动词Heusedtobenervousintheexam.2.表示过去的习惯有时可互换：Whenwewereveryyoung,weusedto/wouldgoskatingeverywinte匚3.表示过去的次数时，不能使用：(7)WewenttotheGreatWallfivetimeswhenwewereyoung.(X)Weusedtoso/wouldgototheGreatWallfivetimeswhenwewereyoung.注：usedtodo的否定式：usedn?ttodo或didn"tusetodo(usedn"t也可写作usen"t)疑问式：rDidyouusetodo?CDidn"tyouusetodo?1Usedyoutodo?1Usedrftyoutodo?II情态动词表推测：1•大多数情态动词（除表，能力、许可、意志，外），都可以表示推测，其程度有差异。按可能性程度的高低排列为：must>will>wouldAoughtto>should完全肯定~完全可能很可能AcanAcouldAmavAmight有可能2.区分情态动词的否定含义：maynot或许不、可能不mightnot可能不can"t不可能mustn"t不许、禁止shouldn"t不应该needn"t不必3•情态动词表推测具体运用：情态动词可以对现在、进行、过去推测。S主+情态动词+be+adj对“性质从特®?啲推测S主+情态动词+be+n对“职业从事物"啲推测S主+情态动词+动词原形对经常性行为的推测S主+情态动词+be+V-ing对进行着的行为的推测S主+情态动词+have+PP对过去的行为的推测情态动词表推测时：1、can只能用于否定句和疑问句2、must只能用于肯定句（它的否定句和疑问句其实就用can来代替了）3、如句中有情态动词+完成吋，定是对过去的推测。4、句屮如有表示不肯定的话语E.gIamnotsure;Idon，tknow之类，常选mny/might的各种形式。4.表示反劝的特殊的表推测形式1）.could+have+P.P.表示木来能做到，但事实上没有做到。Hecouldhavefinishedthetaskontime,buttheheavysnowcame.2）.couldn"t+have+P.P.表示本来不能做到，但已经做到ToShecouldnothavecoveredthewholedistance,butinfactshearrivedaheadoftime.3）needn"t+have+P.P.表示本不必做的，但已经做到了。Sheneedn"thaveattendedthemeetingyesterday,but^hedid. 4.)should/oughtto+have+P.P.表示该做而没有做Theplantisdead.Ishould/oughttohavegivenotmorewater5)shouldn"t/oughtn"tto+have+P.P.表示不该做而做了。Yououghtn^tto/shouldn"thavetakenherbikewithoutpermission.5・注意:must只能用丁•肯定句（它的否定句和疑问句其实就用can来代替了）l.must+have+P.P.表示对过去肯定的推测，“一定是，准是"Theroadiswet.Itmusthaverainedyesterday.2.can+have+P.P.表示对过去的推测邙艮于问句中）Canshehavesaidso?他可能这样说吗？3.can"t+have+P.P.表示对过去的否定推测Hecannothavesaidsuchafoolishthing.III情态动词表推测的反意疑问句1.情态动词表推测的反意疑问句，简单来说，就是以情态动词后的时态为淮，如句子里有明确的时间状语，则以其为准。2.以must为例：E.g.LYoumustbehungrynow,aren^tyou?2.HemustbewatchingTV,isn^the?3Tommusthavelivedherforalongtime,hasn^the?4.Shemusthavearrivedvesterdav，didn，tshe?注：如选择题中(以Shemusthavearrivedyesterday,didiftshe?为例)既有didn"tshe又有hasn"tshe则以didn"tshe?为最佳答案。IV情态动词专项练习与解析一)1.Youreturnthebooknow.Youcankeepittillnextweekifyoulike.A.can"tB.mustn^t)2.Whereismypen?Iit.A.mightloseB.wouldhavelost)3.1wishIyouyesterday.A.seenB.didseeC.needn^tC.shouldhavelostC・hadseenD.maynotD.musthavelostD.weretosee)4・Ididn"thearthephone.Iasleep.D.shouldhavebeenA.mustbeB.musthavebeenC.shouldbe)5・IfmylawyerherelastSaturday,hemefromgoing.A.hadbeen;wouldhavepreventedB.hadbeen;wouldpreventC.were;wouldpreventD.were;wouldhaveprevented)6.Heyoumorehelp,eventhoughhewasverybusy.A.mighthavegivenB.mighthaveC.mayhavegivenD.maygive)7.Ifitforthesnow,wethemountainyesterday.A.werenot;couldhaveclimbedB.werenot;couldclimbC.hadnotbeen;couldhaveclimbedD.hadnotbeen;couldclimb)&Withoutelectricityhumanlifequitedifficulttoday.A.isB.willbeC.wouldhavebeenD.wouldbe)9.Acomputerthinkforitself,itmustbetoldwhattodo.4 A.can^tB.couldn^tC.maynotD.mightnot)10.Jennyhavekeptherword.Iwonderwhyshechangedhermind.A.mustB.shouldC・needD.would)11.Welastnight,butwewenttotheconcertinstead.A.musthavestudiedB.mightstudyC.shouldhavestudiedD.wouldstudy)12.一CouldIborrowyourdictionary?一Yes,ofcourseyou.A.mightB.willC.canD.should)13.Tomoughtnottomeyoursecret,buthemeantnoharm.A.havetoldB.tellC.betellingD.havingtold)14.一Ifhe,hethatfood.一Luckilyhewassenttothehospitalimmediately.A.waswarned;wouldnottakeB.hadbeenwarned;wouldnothavetakenC.wouldbewarned;hadnottakenD.wouldhavebeenwarned;hadnottaken)15.Petercomewithustonight,butheisiftverysureyet.A.mustB.mayC.canD.will)16.1toldSallyhowtogethere,butperhapsIforher.A.hadtowriteitoutB.musthavewrittenitoutC.shouldhavewrittenitoutD.oughttowriteitout)17.1didn"tseeyoursisteratthemeeting.Ifshe,shewouldhavemetmybrother.A.hascomeB.didcomeC.cameD.hadcome)18.—ShallItellJohnaboutit?一No,you.Fvetoldhimalready.A.needn^tB.wouldrTtC.mustn^tD.shouldn"t)19.Whenapencilispartlyinaglassofwater,itlooksasifit.A.breaksB.hasbrokenC.werebrokenD・hadbeenbroken)20.It"snearlyseveno"clock.Jackbehereatanymoment.A.mustB.needC.shouldD.can)21.一Therewerealreadyfivepeopleinthecarbuttheymanagedtotakemeaswell.一Itacomfortablejourney.A.can，tbeB.shouldn"tbeC.mustn^thavebeenD.couldn"thavebeen)22.Johnny,youplaywiththeknife,youhurtyourselfA.won"t;can"tB.mustn^t;mayC.shouldrTt;mustD.can^t;shouldn"t)23.Thefirespreadthroughthehotelveryquicklybuteveryonegetout.A.hadtoB.wouldC.couldD.wasableto)24.—WhencanIcomeforthephotos?Ineedthemtomorrowafternoon.—Theybereadyby12:00.A.canB・shouldC.mightD.need)25.一IstayedatahotelwhileinNewYork.一Oh,didyou?YouwithBarbara.A.couldhavestayedB.couldstayC.wouldstayD.musthavestayed)26.一Willyoustayforlunch?一Sorry,•Mybrotheriscomingtoseeme. A.Imustn"tB.Ican"tC.Ineedn"tD.Iwon"t)27.一AreyoucomingtoJeffsparty?5 A.mustB.wouldC.shouldD.might)28.—Writetomewhenyougethome.A.ImustB.IshouldC.IwillD.Ican)29.1wasreallyanxiousaboutyou,youhomewithoutaword.A.mustrftleaveB.shouldrfthaveleftC.couldn"thaveleftD.needn^tleave)30.一IsJohncomingbytrain?一Heshould,buthenot.Helikesdrivinghiscar.A.mustB.canC.needD・may专项练习(二)1.1didn"tseeherinthemeetingroomthismorning.Sheatthemeeting.A.mustrTthavespokenB.shouldn"thavespokenC.needn^thavespokenD・couldn^thavespoken2.Oneoughtforwhatonehasn^tdone.A.nottobepunishedB.tonotbepunishedC.tonotpunishedD.notbepunished3.Ifyoureallywantyourselftobeingoodhealth,youmustalwayssomuch.A.not;besmokingB.not;havesmokedC・not;tosmokeD.benot;smoking4.Withsomuchworkonhand,youtoseethegamelastnight.A.mustn^tgoB.shouldn"tgobetterC.couldrTthavegoneD.shouldn"thavegone5.MostofthestudentsfeltratherdisappointedattheEnglishparty.Theysaythatitorganized.A.hadbeenB.hadtobeC.musthavebeenD.couldhavebeen6.Fmsurprisedthatheintheexam.A.shouldfailB.wouldhavefailedC.mayhavefailedD.shouldhavefailed7.Thelittlegirltherealone.A.notdaregoB・daresnotgoC.darenotgoD.darenottogo&“Mustwedoitnow?^^“No,you・"A.won，tB.needn5tC.carTtD.don5t9.Hesaidhewouldrathernotitrightnow.A.doingB・todoC.doD.tobedoing10.Youtothemeetingthisafternoonifyouhavesomethingimportanttodo.A.needn"ttocomeB.don"tneedcomeC.don^tneedcomingD.needn5tcome11.Putonmoreclothes.Youbefeelingcoldwithonlyashirton.A.canB.couldC・wouldD.must12.1playfootballthanbaseball.A.wouldratherB.hadbetterC.likebetterD.prefer13.1thoughtyoulikesomethingtoread,soIhavebroughtyousomebooks.A.mayB・mightC.couldD.must 14.Therewasplentyoftimes.She・6 A.mustrTthavehurriedB・couldrTthavehurriedC・mustnothuiTyD.needrfthavehurried14.Theplantisdead.Iitmorewater.A.willgiveB.wouldhavegivenC.mustgiveD.shouldhavegiven15.Youreturnthebooknow.Youcankeepittillnextweekifyoulike.A.can，tB.mustn^tC.needn"tD.maynot16.It^sstillearly,you.A.mustn^thurryB.wouldnlhurryC.maynothurryD.don5thavetohurry17.Pleaseopenthewindow,?A.can，tyouB.aren^youC.doyouD.willyou18.Weforherbecauseshenevercame.A.mustn^thavewaitedB.shouldn"thavewaitedC.mustn^twaitD.needn^twait19.一MayIstophere?一No,you・A.mustrftB.mightnotC.needn^D・worTt20.It^safineday.Let^sgofishing,.A.won"tweB.willweC.don"tweD.shallwe22.1didn^tseeherinthemeetingroomthismorning.Sheatthemeeting.A.mustrTthavespokenB.shouldn"thavespokenC・needn^havespokenD.couldn^thavespoken23.一Pleasedon"tmakeanoise.一・Fllbeasquietasamouse.A.Yes,Iwon"tB.No,Iwon"tC.No,IwillD.Yes,Iwill24.Theyoungmanhasmadesomuchnoisethathenothavebeenallowedtoattendtheconcert.A.couldB.mustC.wouldD.should25.一WhereisJohn?一Heinthelibrary.A.shouldbeB.mustbeC.canbeD.musthavebeen26.Sincetheroadiswetthismorning,lastnight.A.itmustrainB.itmustberainingC.itmusthaverainedD.itmusthavebeenrain27.一Willyourbrotherstayhometonight?一Fmnotquitesure.Hetothecinematonight.D.maybegoingA.mustgoB.cangoC.maygo2&She^salreadytwohourslate.Whattoher?A・canhavehappenedC・shouldhavehappened29.Youmustbeawriter,?A.mustn^tyouB.areyou30.1gotupearlythatmorning,butIA・mustrfthavedoneB・mayhavehappenedD.musthappenC.mustyouD.aren^tyou_sobecauseIhadnoworktodo.B.didn^tneedtodoD.alltheaboveD.hadtoC・needn^havedoneD.carfthavedone31.Hehavecomehereyesterday,buthedidn5t.A.couldB.shouldC.oughtto32.1missedthelastbus,soIgohomeonfoot.A.mustB.havetoC.may 33.Heoughttowinthefirstprize,he?7 A・oughtiftB.shouldn"tC.mustn9tD.bothAandB34.Everyonedohisbestforthemodernizationsofourcountry.A.canB.mayC.shouldD.might35.Let9scleanourclassroom.?A.willyouB・dorTtweC.shallweD.doyou36.Letusplaybasketball.?A.willyouB.don"tweC.shallweD.doyou37.Heaskedmeforthisbookmanytimes.Pleasetellhimthathehaveittomorrow.A.mustB.mayC.shallD.bothBandC38."Yourphonenumberagain?Iquitecatchit：“It"s9568442."A.didn"tB.couldn"tC.don"tD.can"t39.Motherusstorieswhenwewerechildren.A.wasusedtotellB.isusedtotellingC・usedtotellD.usedtotelling40.Shewouldrathermoremoneyonbooksonclothes.A.cost...notB.tospare...don^tC.pay...thanD.spend...than情态动词专项练习与解析一【练习解析】1・C从原题中Youcankeepittillnextweek讦youlike这一信息句可知，“你不必现在还”。2.D从原题中Whereismypen?这一信息句可告诉考生，“笔丢了J丢的动作是过去发牛的。因此用must+havedone表示对过去事实的肯定猜测。3.C原题屮的yesterday这一信息词告诉考生，在wish后的宾语从句屮，用过去完成时，表示与过去事实相反的愿望。4.B从原题中的Ididn"thearthephone.这一信息可以判断出，用musthavedone表示过去事实的准确的肯定猜测。5.A从原题中lastSaturday这一信息词可知，条件句中用表示与过去事实相反的过去完成时，主句用would+havedone。6.Amighthave+过去分词，在次是虚拟语气，表示“本来可以给你更多的帮助二而事实则是帮助较少。7.C从原题中的yesterday这一信息词暗示考牛，该句应选用与过去事实相反的过去完成时,Ifithadnotbeenfor...64要不是因为"。8.D原题中的Withoutelectricity相当于一个条件句：Iftherewerenoelectricity,故主句用humanlifewouldbequitedifficulttoday.9.Acan可以表示一种客观上的能力，本句cant表示“不能，不会”。10.B从原题总的t4Iwonderwhyshechangedhermind,,4t^不知道为何他改变了主意了。”这句话告诉考生Janny没有守诺言。因此，用should+havedone,表示“过去本应该做某事，而实际上没有做雹11・C可参看10题。意思是：“昨晚本应该学习，但是却去听音乐会了。”9.C原题中的could不是过去时，而表示一种委婉、客气的礼貌用语。因此用could提问时，用can回答。同样用would,might提问,用will和may回答。［注意］①—Wouldyouratherdosuchathing?—Yes,Iwould.②一Wouldyoulikesometea?一Yes,Iwould.这两个对话屮的wouldrather,wouldlike是惯用法，故不能用will來回答。因为在这两个句型中，will不能去替换wouldo10.A可参看10、15题。该句意思是：“汤姆本来不该告诉我你的秘密，但他没有伤害你的意思。"oughtnottohavedone=shouldn"thavedone 9.B从答语中的Luckilyhewassenttothehospitalimmediately这一信息句可提示考生，条件句应填表示与过去事实相反的时态。15・B从原题中的butheisn?tverysureyet这一信息句可喑示考生，Petei•当晚来的可能性不大。A是“准来，肯定来”，D是“将要来”。16.C可参看10、11>13题。“本应该”而事实上没有17.D从原题中Ididn"tseeyoursisteratthemeeting和后文shewouldhavemetmybrother这两个信息句可知，if条件句中应填与过去事实相反的过去完成吋。可参看6、7、14题。18.A你不必告诉他。因为Fvetoldhimalready这一信息句已喑示考生了。19.C当as讦引导虚拟语气的句子是，如果主句与从句中的谓语词所表达的动作同时发生时，as讦后接一般过去时。例如：Hewalkedas讦hewerelame.如果从句中的谓语动作发生个在主句谓语动作之前，则用过去完成时。例如：Hetalkedasifhehadknownthesecret.不论主句中的谓语是现在时还是过去吋。20.C只要考生抓住nearly一词和后文atanymoment（随时的意思）这两个信息词语，就能很快选出C项，表示逻辑推测，意思是“快七点钟了，杰克一会儿就该到了。”21.D根据句意，是对过去情况的推测当时决不可能是一次舒服的乘车。Fust表示对过去的推测只能用于肯定句。22.Bmustit表示“禁止Smay表示“有可能S句子的意思是「你不可以玩刀，可能会伤你自己「23・D该题在考考生could与wasableto间的区别。Wasableto表示在困难的情况下，经过一番周折而“能……"，并且成功地做了。24.B该题考查情态动词should表推测的用法。Can和might都可以表示可能性，用might则语气更加不肯定。Need表示“需要”、"必需雹Should可以表示推测,结合实际，合乎逻辑，意为“应当”、"该根据第一个说话者说的Ineedthemtomorrowafternoon的语境，可以确定正确答案为B。25.A该题在考査悄态动词+不定式的完成式叩勺用法，从会话的语境看，空口处应填“could+have+过去分词”表示过去本来能做到的事而事实上没有做到。26.B该题考查表示请求的英语口语，用will来向第二人称提问的疑问结构，是表达一种意愿和请求，是以疑问的形式来表达较为婉转的祈使语气，意思是“请你……，好吗？”，对于这种问句的肯定答语可用Sure!Certainly!Yes,ofcourse.Fdbegladto等；否定冋答通常是Fmsorry,Ican"t.No,FmafraidIcan"t.I"msorry,but...I"dliketo,but...等。27・Dmight表示“可能性"。28・C意思是“我会的雹对祈使句的肯定回答。29.Bshouldn^havedone为本来不该做某事，而事实上做了。30.D用maynot可表示“可能不二而cannot则表示断然的否定推测“不可能"。A,C意思不符。专项练习二答案与解析1.D.must表示推测时不用于否定句；shouldn,thavedonesth.表示“本不应该做某事而实际上做了”;needn^havedonesth.表示“木来不必做某事而实际上做了"；couldn^havedonesth.表示"不可能做过某事根据题意，选D。2.A.情态动词ought后要接带to的不定式,oughttodo的否定式是oughtnottodo,所以答案是A。3.A.mustnotalwaysbedoingsth.表示"不要老是做谋事”，含有埋怨、指责、反感等感情色彩。4.D.题中的A项和B项都指现在情况；couldn^havegone表示"不可能去过”；shouldn^havegone表示“木不应该去而实际上去了S根据题意，选D。_5.D.couldhavedonesth.表示"本来能够做某事而实际上未能做成"。6.D.should可用于表示惊奇、感叹、不满等感情色彩的句子，如指过去的动作，则要用shouldhavedonesth.Would和may通常不带感情色彩。7.C.题中的dare是情态动词，后接不带to的不定式，主要用于疑问句、否定句和条件句中。 &B.must开头的疑问句，否定答语用needn"t或dorfthaveto。9.C.wouldrather通常也视为情态动词（组），后接动词原形，其否定形式为wouldrathernote10.D.need作为情态动词，其否定形式为needn?t；作实义动词时，其否定形式为don^（doesn^）needtodoo11.D.must用在肯定句中表推测时，语气比could,would等肯定得多。此处“must+不定式进行式”表“想必正在......"之意。12.A.wouldrather...than...»意为"宁愿（做）而不（做）13.B.由句意可知，这是对过去发生的事情不太有把握的推测。14.D.needn"thavedone意为"过去不必做而做了某事15.D.shouldhavedone表示“过去应该做而没有做某事”。16.C・can"t（不能）,mustn"t（不准），maynot（不可以）,均不合题意。17.D.don"thaveto=needn"t18.D.will用在第二人称的疑巴句中，为询问（或征求）对方的意愿或向对方提出请求之意。19.B.shouldnothavedone表示“过去不应该做而做了某事”，含有“后悔”、“责备"、“劝告”，“批评”之意。20.A.may开头的疑问句，否定答语常用mustrft。21.D.疑问句中shall用于第一、三人称，用来征询对方的意见。22.D.推测“她不可雀在会上发言Jmust表示推测时，不能用于否定句中。23.B.will在此处表示“意志（向）”。24.D.shouldnothavedone表示“过去不应该做而做了某事二含有“后悔”、“责备”、“劝告”，“批评”之意。25.B.mustdo表示对现在的事实进行推测。26.C.mu辻havedone用于对过去发生的事情进行推测，且较有把握。27.C.表示推测时，must比may语气肯定。28.A.can表推测，只用丁否定句和疑问句中。29.D.must表示推测时，其后的反意问句有两种情况：①对现存状态（现在的事实）进行推测时，反意疑问句中动词用其一般现在形式。②对过去发牛的事情进行推测时，若有表过去的时间状语，反意问句用动词的过去式。30.C.needn?thavedone表示“过去不必做而做了某事二若表示“不必做某事（且实际上未做）“则用"didn"t/don"t/doesn"tneedto."31.D.A表示“本能够”,B,C表“本应该程32.D.haveto表示客观上要求做某事，must表示主观上认为必须做某事。33.D.oughtto的反意问句应用oughtrft或shouldn^开头。34.C.should含“按理应该做……”、“有义务做……”之意。35.C.Lefs中的us—般包括对方在内。36.A.Letus中的us—般不包括对方在内。37.D.may和shall均可表“允诺38.A.由句后得知句意为“我开始没听清楚对方的电话号码"，为对过去的事实或发生动作的表述。39.C.usedtodo"过去（常）做某事"，beusedtodoing"习惯于做某事40.D.wouldrather后接动词原形。Spend...onsth.为常用结构。