情态动词情态动词的定义：本身具有一定的词义，表示某种感情和语气。Youcan’tdoitlikethat.(表示责备）常见的情态动词有can,could,may,might,must,need,haveto,should等.所有的情态动词后面都接动词原形.--Icanswim.--Hehastogonow.1.can能够,会,可以--IcanspeakEnglishwell.2.can用来表示否定推测和疑问推测--Thatcan’tbeourEnglishteacherbecauseshehasgonetoShanghai.--Canitbetrue?2.may可以,可能,也许--Youmaygowithme.--MayIborrowyourpen?--Yes,youmay.No,you_______________3.must必须mustn’t严禁,禁止,不许Eg:Imustlearnhowtowork.Youmustn’tplayinthestreet.---MustIfinishtheworknow?---Yes,youmust.No,youneedn’t/don’thaveto(不必）.此外must用于肯定推测,表示肯定是Eg:Thebookmustbelongtohimbecausewecanseehisnameonit.4.need(需要)既可做实义动词也可做情态动词实义动词needtodosth需要做某事Eg:Ineedtobuyabighouse.---Doyouneedtobuyabighouse?---Yes,Ido.No,Idon’t.2)情态动词needdosth需要做某事Eg:Ineedbuyabighouse.5.haveto不得不Eg:It’seighto’clock.Ihavetogonow.Idon’thavetogonow.（否定形式）haveto和must的区别:haveto表示客观因素Eg:Weareverygladattheparty,butit’s11,sowehavetoleavenow.must表示主观因素Eg:Wemuststudyhardtofindagoodjobforourselves.6.hadbetter最好、、、You’dbetterdosth你最好做某事Eg:You’dbetterbuythebook.否定形式：You’dbetternotdosth你最好不要做某事Eg:You’dbetternotrunintheclassroom.【实例解析】例1：--CouldIborrowyourdictionary?—Yes,ofcourseyou____.A.mightB.willC.canD.should例2：____youmindmysmokinghere?A.ShouldBCouldC.MightD.Would例3：--MustIstartatonce?—No,you____.A.needn’tB.mustn’tC.can’tD.won’t【考点直击】(1)John___cometoseeustonight,butheisn'tverysureyet.A.mayB.canC.hastoD.must(2)MayItakethisbookout?No,you___.A.can'tB.maynotC.needn'tD.aren't(3)You'dbetter___latenexttime.A.nottobeB.notbeC.won'tbeD.don'tbe(4)He___beintheclassroom,Ithink.No,he___beintheclassroom.Isawhimgohomeaminuteago.can;maynotB.must;maynotC.may;can'tD.may;mustn't(5)Hehadtogiveuptheplan,___he?A.didB.didn'tC.doesD.doesn't(6)Hecomeheretomorrow.A.neednotB.doesn’tneedC.needn’ttoD.don’tneed(7)It’sraininghardoutside,I______stayathome.A.mustB.havetoC.mayD.can