初中情态动词

情态动词无人称和数的变化；不能单独使用，必须与其后的动词原形构成谓语情态动词用法归纳EvelynJingYoumustn'ttakepicturesofmine!你不能给我拍照！Youshouldwashyourhandseveryday.Youhadbettergotothedoctor.04表推测03命令禁止02表能力01委婉请求05情实共存CONTENTS情态动词肯否不一06•Youmustn'ttakepicturesofmine!•Youshouldwashyourhandseveryday.•Youhadbettergotothedoctor.什么是情态动词定义：表示说话人的态度和看法原则：1.不能单独使用，后面要接动词原形（do）构成谓语2.没有人称和数的变化情态动词•情态动词（Modalverbs）本身有一定的词义，表示语气的单词。•但是不能独立作谓语，只能和动词原形一起构成谓语。情态动词用在行为动词前，表示说话人对这一动作或状态的看法或主观设想。•情态动词虽然数量不多，但用途广泛，主要有：can(could),may(might),must,need,oughtto,dare(dared),shall(should),will(would)情态动词的含义和特征•它只有情态意义，即它所表示的是说话人对动作的观点，如需要，可能，意愿或怀疑等。•情态动词有以下特征：•1）在形式上，情态动词没有实义动词的各种变化，只有could，would，hadto，was（或were）to，might等几个过去式，其他如must，oughtto等的过去式皆与现在式同型。•2）在意义上，大多数情态动词有多个意义，如can可表“能够”“可能”“允许”等。•3）在用法上，情态动词与助动词一样，后面须接动词原型，构成谓语动词。委婉请求maymightcancould•1._____Icomein?•2._____Iborrowsomemoney?•3._____Ihelpyou?•4._____youpleasehelpme?情态动词“can”和“may”的区别•can可以用来表示一个人做某事或谈论任何可能性的能力。“能够”•may习惯于接受或给予他人许可。“可以”•can和may用来寻求或获得许可，但是may更常见和正式。•一般来说，我们使用单词can来非正式地询问某些东西。may可用于正式要求或允许某事。•could比can更委婉•might比may更委婉委婉请求maymightcancould•1._____Icomein?•2._____Iborrowsomemoney?•3._____Ihelpyou?•4._____youpleasehelpme?MayMightCanCould委婉请求•1.----MayIcomein?----Yes,youcan.•2.----MightIborrowsomemoney?----No,youmaynot.•3.----CanIhelpyou?----Yes,please.//----Thanks,buticanmanageit.4.Couldyoupleasehelpme?----Yes,withpleasure.----Sorry,Ican't.Youhadbettertrytoasksomeoneelse.•1.----Mum,_____Iplayoutsidewithmyfriends?•----Yes,youcan,butyouhavetofinishyourhomeworkfirst.•A.wouldB.mustC.mayD.need•2.CanIborrowyourdictionary?•Yes,ofcourse,you______.•A.canB.mustC.mayD.should•1.----Mum,_____Iplayoutsidewithmyfriends?•----Yes,youcan,butyouhavetofinishyourhomeworkfirst.•A.wouldB.mustC.mayD.need•2.CanIborrowyourdictionary?•Yes,ofcourse,you______.•A.canB.mustC.mayD.should表能力can表能力，能，会（=beableto)Icanswim.Ican'tfly.IcoulddothiswhenIwasyoung.I'llbeabletogoswimmingthisafternoon.表能力can表能力，能，会（=beableto)Icanswim.Ican'tfly.IcoulddothiswhenIwasyoung.I'llbeabletogoswimmingthisafternoon.can只有一般现在和一般过去式（could）beableto时态更多，有将来，过去完成等时态•2.----________youplaygolf?•----No.ButIcanplaytabletennis.•A.CanB.MayC.MustD.Should•3.Workhardandyou______enteryourdreaminguniversityoneday.•A.canB.couldC.isabletoD.willbeableto•2.----________youplaygolf?•----No.ButIcanplaytabletennis.•A.CanB.MayC.MustD.Should•3.Workhardandyou______enteryourdreaminguniversityoneday.•A.canB.couldC.isabletoD.willbeableto命令禁止musthavetomustn'tdon'thaveto命令禁止musthavetomustn'tdon'thaveto•1.Heismybestfriend,soI___________helphim.•2.He___________gettoschoolbefore8o'clock.•3.We___________sleepinclass.•4.We___________arrivesoearly.命令禁止musthavetomustn'tdon'thaveto•1.Heismybestfriend,soI___________helphim.•2.He___________gettoschoolbefore8o'clock.•3.We___________sleepinclass.•4.We___________arrivesoearly.musthastomustn'tdon'thaveto命令禁止must必须，一定，表达说话人的主观看法haveto不得不，强调客观需要mustn't禁止，不准，绝对不可以don'thaveto没必要•4.----Mum,canIwearmyjeanstoschool?•----No,you________wearyourshooluniform.That'stheschoolrule.•A.canB.can'tC.havetoD.may•4.----Mum,canIwearmyjeanstoschool?•----No,you________wearyourshooluniform.That'stheschoolrule.•A.canB.can'tC.havetoD.may表推测1.Itcan'tbe2.Itmay/mightbe3.ItmustbeGuess！表推测1.Itcan'tbe2.Itmay/mightbe3.ItmustbeGuess！表推测1.Itcan'tbe2.Itmay/mightbe3.ItmustbeGuess！表推测1.Itcan'tbe...2.Itmay/mightbe...3.Itmustbe...4.Itisacat!Guess！一定不：can't完全否定的猜测可能：may,might可能不：maynot,mightnot一定：must完全肯定的猜测•5.----IthinkMissGaomustbeinthelibrary.Shesaidshewouldgothere.•----No.She______bethere.Ihavejustbeenthere.•A.can'tB.mustn'tC.needn'tD.wouldn't•6.You_______behungrynowbecauseyoudon'teatanythingtoday.•A.canB.mustC.needD.might•5.----IthinkMissGaomustbeinthelibrary.Shesaidshewouldgothere.•----No.She______bethere.Ihavejustbeenthere.•A.can'tB.mustn'tC.needn'tD.wouldn't•6.You_______behungrynowbecauseyoudon'teatanythingtoday.•A.canB.mustC.needD.might情实共存--need可以当情态动词也可以当实义动词Ineedn'thelphimdohishomework.Heneedstodohis.情态动词肯定：need/daredo否定：need+not/dare+notdo实意动词肯定：need/daretodo否定：don'tneed/daretodo无三单变化后面+do否定后加not有三单变化后面+todo否定用助动词need的用法•1)实义动词,意为需要；必要,后面可接名词、动名词或动词不定式等作宾语。注意needdoing表示被动意义,相当于needtobedone。例如：•Ineedadictionary,soIneedtogotothebookstore.•我需要一本词典,因此我要去趟书店。•Howoftendoesyourhairneedwashing(needtobewashed)?•你的头发需要多久洗一次？needtodosth需要做某事（实义动词）当need为实义动词，需要的意思时，后面接动词不定式，即needtodosth需要做某事。疑问句时Didsb.needtodosth.?need的用法•2)情态动词,通常用于疑问句和否定句中,后接动词原形。•这时need没有人称和数的变化,也没有时态的变化。例如：•It'sonlyeighto'clock.Needyougosoearly?才八点。你需要去这么早吗？•Youneedn'ttellhimaboutitasIhavetoldhim.你不必跟他说那件事,我已经告诉他了。•needdosth必须做某事（情态动词）•1.情态动词不能用助动词(did)提问，直接把情态动词提前。•----NeedIgotoschool?•----Yes,youmust.•2.情态动词后面加动词原形（do）•3)needn'tdo与needn'thavedone的区别：两者都表示不必做......•needn'tdo表示现在或将来不必做；•needn'thavedone表示过去(本来)不必做(而事实上已经做了)。•Youneedn'tcarrythedesksoutoftheclassroomwhenyoucleantheclassroom.•你打扫教室时不必把桌子搬到教室外。•Youneedn'thaveboughtsuchabigTVasittakestoomuchroom.•你本来不必买这么大的电视,它占据的空间太大了(而事实上已经买了)。need的用法•7.----______yougohomeatnightbyyourself?Itisdark!•A.CanB.DareC.MayD.should•8.Didheneed_______then?•A.leaveB.leavingC.toleave