情态动词基本用法.pptVIP

Whatare情态动词(modalverbs)?情态动词的特点情态动词有一定的意义无人称和数的变化通常不带to,后接动词原形表示说话人的语气或情绪情态动词备考方向:5%55%30%10%各情态动词的基本用法;情态动词在特定语境中的用法易混淆情态动词的辨析;虚拟语气中情态动词的用法.Howmanymodalverbscanyouremember?modalverbs添加标题have/hadto添加标题will/would添加标题can/could添加标题may/might添加标题shall/should添加标题must添加标题need添加标题dare添加标题oughtto添加标题usedto添加标题1.can/could表示能力Hecanplaytabletennisquitewell.表示事物一时的特征,理论上的可能性It’salwayswarmhere,butsometimesitcanbeverycold.He’sgood-tempered.However,hecanbehardtodealwithwhenoffended.Evenanexperiencedteachercanmakemistakes.3)表示许可/允诺---Can/CouldTomusethecar?---Yes,hecan.Youcanhavemyseat.Iamgoingnow.4)表示推测1)---Someoneisknockingatthedoor.Whocanitbe?CanitbeScarlet?---No,itcan’tbeher.ShecalledfromTokyojustnow.2)Hecannothaveforgottenit.3)Theaccidentcouldhavebeenavoided.2.may/might1)表示请求\许可---May/MightIcomein?---Yes,youmay.2)表示可能性的推测Herappearancehaschangedsomuchthatyoumaywellnotrecognizeher.It’ssolate.Ithinghemay/mighthavegonetobed.Youmighthavegivenhimmorehelp,butwhydidn’tyou?3)may用于祈使句表示祝愿Mayyousucceed!Mayyoureturninsafe!3.must1.必须MustIsay“sorry”?Yes,youmust./No,youneedn’t.Youmustseeadoctor.2.猜测“肯定,准是”ShemustbewatchingTVnow.Theremustbesomemistake.Itmusthaverainedlastnight.Thegroundissowet.3.“偏要,硬要”Ifyoumustsmoke,pleasegoout.4.否定,表示“禁止”Youmustn’tplaywithfire.Youmayhurtyourself.must对比haveto1)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.Hesaidthattheymustworkhard.2)haveto有人称、数、时态的变化，而must只有一种形式。Hehadtolookafterhissisteryesterday.3）在否定结构中：don‘thaveto表示“不必”mustn’t表示“禁止”Youdon‘thavetotellhimaboutit.Youmustn‘ttellhimaboutit.4.Shall的用法(1).Shall常用于第一人称表示简单的将来Whensha