GrammarModalverbs情态动词(I)-_______I……?-Yes,you_____./No,you_______一、表请求的情态动词-May……?-Yes,youmay./No,you_______/hadbetternot.1.Can/CouldCouldcancan't.2.may\mightmustn’tShallIopenthewindowforyou？Shallhefetchsomewaterforyou？Yes,please.\No,youneedn’t.3.shall在疑问句中,用于一、三人称，用来表示请求或征求意见。我可以……?他可以……?1.—______Igohomenow,sir?—No,you____.Youshouldfinishtheworkfirst.A.Might;wouldn’tB.May;hadbetternotC.Must;mustn’tD.Need;mustn’t2.—CouldIuseyourbike?—Yes,surelyyou______.A.mightB.willC.canD.should3.—______heuseyourbike?—Certainly.Hereisthekey.A.ShallB.MustC.WillD.DoesBCA二、表猜测的情态动词must表猜测，用于肯定句中can表猜测，常用于否定、疑问句中can’t不可能maynot可能不mustn’t可不能；禁止；不允许进行式：must/should/can/could/may/mightbedoingsth.（对正在进行的动作的猜测）一般式：must/should/can/could/may/mightdosth.（对一般情况的猜测）•Hurryup!Theymustbewaitingforusattheschoolgate.•Someoneisknockingatthedoor.Whocanitbe?•快点！他们一定在校门口等我们呢。•有人在敲门。可能是谁呢？1.Peter____comewithustonight,butheisn’tverysureyet.A.mustB.mayC.canD.will表猜测must肯定，一定may/might\could可能can用于否定、疑问句中2.—Areyoucomingfordinner?—I’mnotquitesure.I______gotomyuncle’sinstead.A.mustB.wouldC.shouldD.mightBD4.Jack,you_____playwiththeknife,you____hurtyourself.A.can’t,mayB.shouldn’t,canC.mustn’t,mayD.won’t;shouldn’t3.Herbrother____beathomenow,becausehewasseeninthestadiumjustnow.A.mustn’tB.needn’tC.can’tD.shouldn’t表猜测，must的反义词是can’t不可能mustn’t可不能，禁止，不允许CC1.(06全国卷)There’snolightnow.They_____beathome.A.can’tB.mustn’tC.needn’tD.shouldn’tA三、must/haveto表示“必须”的区别1.-Must….?-Yes,youmust.-No,youneedn’t/don’thaveto.1.Idon’tlikethisTVset.We______buyanewone.2.Therewasnomorebus.They_______walkhome.2.must主观看法，haveto客观需要。haveto用于更多时态。musthadto四、can/beableto的区别She______________singthesonginEnglish.Thismachine______makeyoufeelcomfortable.1.can,beableto都可表示“能力”can的主语是人或物,beableto的主语是人We________________finishtheworksoon.I____________________(not)seeafilmsincelastyear.2.can只用于现在式和过去式(could)。beableto可以用于各种时态。can/beabletocanwillbeabletohaven’tbeenableto3.表示成功地做了某（件具体的）事时，只能用beableto,不能用could。Thoughthefireisbig,they__________runaway.(could,beableto)wereabletoMayyousucceed!MayGodblessyou!五、may放在句首,表示祝愿。六、should表示惊讶的语气,“竟然…”Itisunfairyoushouldtreatmelikethat.Weshallmeetwhatevermayhappen.七、shall用于肯定句。表示命令、承诺。“一定…”八、情态动词+havedone表示对过去发生事情的可能性猜测musthavedonesthshouldcan/couldmay/mighthavedonesthhavedonesthhavedonesth一定做了某事本应该做某事（却没做）本可以做某事可能做了某事Can’t/couldn’thavedonesth不可能做过某事1.You______betired.--You’veonlybeenworkforanhour.A.mustn’tB.won’tB.C.maynotD.can’tD2.Thefirespreadthroughthehotelveryquicklybuteveryone______getout.()A.hadtoB.wouldC.couldD.wasabletoD3.-Theroomisdirty._____wecleanit?-Ofcourse.A.WillB.ShallC.WouldD.Do4.Mypenhasdisappeared(不见).Who______havetakenit?A.mustB.wouldC.couldD.shouldBC5.Youcan’timagine(想像)thatawell-behavedgentleman_____besorudetoalady.A.mightB.needC.shouldD.wouldC6.You_____nevergetmyhelpifyoudosuchabadthing.A.shallB.mayC.mightD.shouldAThiscakeisverysweet.You______alotofsugarinit.A.shouldputB.couldhaveputC.mightputD.musthaveputOh,I’mnotfeelingwellinthestomach,I____somuchfriedchickenjustnow.A.shouldn’teatB.mustn’thaveeatenC.shouldn’thaveeatenD.mustn’teat
