情态动词can-和cannot;-may和maynot-;-must和mustnt

Modelverbs情态动词情态动词本身有一定的词义，但需与动词原形一起使用，给谓语动词增添情态色彩，表示说话人对有关行为或事物的态度和看法，认为其可能，应该或必要等。情态动词后面通常加动词原形。A1canandcannot情态动词can与cannot我们用can表示某人具备某种能力做某事。如：Icanplaybasketball.Wecanfinishtheworkin20minutes.其否定形式为cannot或can’t.如:Icannotswim.I’mafraidIcan’tthinkofmoreexamplestosupportthisargument.疑问句中，把can提到句首，将can与主语的位置对调。Canyouspeakanyforeignerlanguages?—CanyousolvethisMathsproblem?—I’msorry,Ican’tA2mayandmaynot情态动词may与maynot在请求对方的许可，或是准许你做某事时，常用情态动词may和can.may比较正式，can较常用且更口语化一些。如：—MayIleaveworkearlytoday?—我今天可以早点下班吗？Yes,may—你可以—YouNo,maynot—你不可以—CanIopenawindow?—我可以开扇窗吗？Yes,can—你可以—YouNo,can’t—你不可以Youmay/canusemydictionary.你可以用我的词典。Youmaynot/cannotusemycomputer.你不可以用我的电脑。A3mustandmustnot情态动词must与mustnotmust用以表示“必须做某事”或“一定要做某事”，具有强制性，表达一种责任或义务或表示很有必要做某事；或在提出建议时使用，意为“应该；得”。如:Wemustobeytheschoolrules.Thewindowsareverydirty.Imustcleanthem.Wemustgotothebanktoday.Wehaven’tgotanymoney.It’safantasticfilm.Youmustseeit.must的否定形式是mustn’t,表示“禁止”，“决不允许”，具有强制性。如:Imusthurry,Imustn’tbelate.Youmustn’tforgettophoneJulia.must用于一般疑问句中，其肯定和否定回答应引起我们的注意。—MustIgonow?—我们现在一定要走吗？Yes,must—是的；我们一定要走—weNo，mustn’t—不，我们不可以走。—MustIfinishreadingthebookthisweek?Yes,must—youNo,needn’t典型例析（）1.—_________yourAmericanfriendeatwithchopsticks?—Yes,buthecan’tusethemwell.A.CanB.ShouldC.Must【解析】A本句表示能力“会；能够”，can符合题意。（）2.Everyone________gothroughthesecuritycheck(安检)whenenteringtheWorldExpoPark.A.canB.mayC.mustD.ought【解析】C本句表示“必须，一定要”，must符合题意。（）3.—Thewinnersoftheraceisatallandthinboywithglassed.—Thenit_______bemyfriend,Mike,wholooksveryfat.A.mightB.can’tC.don’tD.Should【解析】B由上下文语境可知本句的意思是“那么他不可能是我的朋友”，表推测“不可能”时用“can’t”()4.—MustIgototheshopwithyou,Mum?—Err…Icanmakeitmyself,Mike.You______gowithme.A.mustn’tB.shouldn’tC.wouldn’tD.needn’t【解析】D由上下文语境可知本句的意思是“你没必要去”，表示“不必要”可用needn’t或don’thaveto()5.—Thisdeskistooheavy.I_______moveit.Couldyouhelpme?—NoproblemA.canB.can’tC.shouldD.shouldn’t【解析】B句意为“这桌子太重，我没法移动它。”表示“没能力做某事”应用can’t()6.—MustIfinishmyhomeworkrightnow、—No，you_________.A.needn’tB.maynotC.mustn’tD.can’t【解析】A此处must提问表示“必须”，否定回答只能用needn’t或don’thaveto.()7.—________Itakesomephotosinthehall?—No，you__________.A.Can;needn’tB.Must;mustn’tC.Could;won’tD.May;mustn’t【解析】D句意：“我可以在大厅里照相吗？”“不，不可以”。表示请求许可时用can或may,其否定回答用can’t或mustn’t()8.—_________Iuseyourruler,Lingling?—Sure.Hereyouare.A.MayB.WouldC.NeedD.Must【解析】A根据句意“用一下你的尺子可以吗？”可知此处是表示请求许可，可用may和can.考点专练一用can,may或must的适当形式填空。1.__________Iaskyouaquestion?2.Attendingaball________beexciting.3.Michael_______beapoliceman,forhe’smuchtooshort.4.—AreyoucomingtoJeff’sparty?—I’mnotsure.I_______gototheconcertinstead.5.Henevertakesataxi.He_______beverypoor.6.Ithoughtyou________likesomethingtoread,soIhavebroughtyousomebooks.7.Look!I__________standonmyhands.8.He______havebeentoShanghai.HeknowssowellaboutShanghai.9.Theplayisnotinteresting.Ireally_________gonow.10.She______likethisplace.11.—CouldItakethisseat,sir?—Yes,you_________.12.It________beveryhotinShengyanginsummer.13.Ihavejustmetherinthesupermarket.She______beinShanghainow.14.Mary_________phone.Ifshedoes,couldyouaskhertoringlater?15.______youbehappyandhealthy.16.We_______spitinpublic.二选择正确的情态动1.Baby_______(can,cannot)run.2.Dogs_________(can,cannot)understandsimpleorders.3词。1.Ab.Johnpracticesrunningeveryday,sohe___________(can,,cannot)runveryfast.4.You___________(can,cannot)passthetestifyoudon’tworkhard.5.Camels___________(can,cannot)liveinthehotareas.6.Camels___________(can,cannot)gowithoutwaterforalongtime.三根据所给情景，仿照例句写出问句。1.Theradioisveryloud,andyouandyourbrotherarestudying.A:Mayweturnofftheradio?B:Yes,pleaseturnitoff.2.Youandyourfriendseesomelosttourists.A:_____________________________________________________B:Oh,yes,pleasehelpus.3.Youseefourofyourfriendsplayingbasketball.A:_____________________________________________________B:Yes,pleasejoinus!Weneedafifthplayer.4.Youwanttohavesomeicecream,butyouhavenomoney.A:______________________________________________________B:Ofcourseyoucanborrow20yuan.5.It’squitehotintheroom,andtheairconditionerisoff.A:______________________________________________________B:Yes,youcanturnitoff.6.You‘dliketoordersomedishesinarestaurant.A:______________________________________________________B:Yes,ofcourseyoucanhavethemenu.7.Youdon’tknowanEnglishwordwhenyouarereading.A:_____________________________________________________B:Yes,pleaseusemydictionary.四用youmust或youmustn’t完成下面的句子。1.__________________studyhardbeforeyourexams.2._________________parkyourcarhere.It’sagainsttherule.3._________________eatmorehealthyfood.4.________________wearathickcoatwhenitiscold.5.________________swimafteraheavymeal.6._______________dosomewarm–upexercisesbeforegoingtoswim.五用适当的情态动词填空。1.________Icomein?2.I_____speakalittleFrench.3._________Ihavealookatyourpictures?4.Thechild________rideabike.5.Theredlightison.We_______stop.6.________shefinishitinthreehours?7.I________driveacar,butIwilllearntodrivewhenIgrowup.8.You______borrowthreebooksatatime.六用must,mustn’t,may,maynot,can或can’t填空。ThisisMrsLee’sfirsttriptoCanada.She(1)_____________onlyspeakalittleFrenchandalittleEnglish.Today,shewi