高三英语语法情态动词(课件)

情态动词●ThebasicusesofModalVerbs6、dare7、need8、oughtto二、补充说明三:情态动词用于推测四:情态动词+havedone的用法一:基本用法1、can/could2、may/might3、must4、shall/should5、will/would可兼做行为动词的情态动词：need、dare情态动词(+动词原形)行为动词.needdare1.无人称和数的变化;2.尤其用于：*否定句及疑问句中;*在if/whether之后;*或与hardly,never,noone,nobody连用;3.常以needn’t和daren’t的形式出现;4.dare有其过去时dared.多用于肯定句;(sb.)needtododaretodo(sth.)needtobedone(sth.)needdoing一、1.can1.表示能力Theparrotcanspeakthreelanguages.2.表示允许CanIborrowthebookfromthelibrary.3.表示可能性ShanghaicanbeverycoldinMarch.could为can的过去式；语气更委婉2.can与beableto1.can表示习惯能力，而beableto表示经过努力而做成了某事。2.在否定结构中，二者可以互换。3.can/could+have+p.p1.在否定、疑问句中表示“对过去发生行为的可能性猜测。2.在肯定句中表示“本来可以做而未做”1.Thedoorwaslacked.Shecouldn’thavebeenathome.2.Youcouldhavebeenmorecareful,butyouweresocareless.二、1.may1.表示可能性2.表示允许3.表示祝愿might为may的过去式；语气更委婉2.may/might+have+p.p1.在否定、肯定句中表示对过去动作的推测“也许是……”2.might+have+p.p表示虚拟，表“劝告、责备之意。”eg.1.Shemaybestillwaitingforus.2.MayIcomein?3.Mayyouhaveahappyholiday.eg.1.Hemighthavespokentoheryesterday.2.Youmighthavetoldmeearlier.三、1.must1.表示肯定的猜测,但只用于肯定句，2.而mustn’t表示“禁止、不准”2.must、haveto与havegotto1.Must表示主观2.Haveto表示客观需求3.Havegotto多见于口语3.must+have+p.p对过去事情的肯定猜测。Eg.Theroadidwet.Itmusthaverainedlastnight.四、1、shall/should1、第一、三人称疑问句中表示“请求或征求对方意见。Eg.ShallIgetyouacupofcoffee?2、第二、三人称陈述句中1、表示允诺“会（得到）。2、表示命令/警告威胁“该回必须”2、shall/should+have+p.poughtto表示本应该做而未做。should为shall的过去式语气更委婉eg.Youshouldhavebeenfiveminutesago.五、1、will/would1、表示意愿I’lltrymybesttoovercomethedifficulty.2、表示意图Whatwillyoudo?3、表示请示Willyouhelpmetoputthesebooksinorder?4、表示习惯动作Shewillsitforhourswithoutsayingaword.2、could与usedto1、would后只能接表示动作的动词。2、usedto则还可以接表示状态的动词。eg.Heusedtobeaworker.补充说明1.、情态动词的过去式与原形相比，多点礼貌，少点冒昧，语气更为委婉。情态动词在一般疑问句中的回答：①Canyousing?②MayIcomein?③MustIhandinthebooknow?④NeedIfinishitnow?Yes,Ican.No,Ican’t.Yes,youmay.No,youmustn’t.Yes,youmust.No,needn’t/don’thaveto.Yes,youmust.No,youneedn’t.★表示推测——情态动词的重要用法.肯定的推测可能的推测否定的推测疑问的推测must/should对将来对现在对过去情态动词may,mightcan’t,couldn’tcan,could+V.+V.+havedone常见mustbe+bedoing+V.+V.+havedone+bedoing可以用not表示“可能不”+V.+V.+havedone+bedoing+V.+V.+havedone+bedoing★Choosethebestanswers:1.Ithoughtyou______likesomethingtoread.SoIhavebroughtyousomebooks.A.oughtB.mightC.wouldD.must•2.–ThatmanmustbeSarah’shusband.--No,he_____beherhusband.Sheisstillsingle.A.can’tB.mustn’tC.maynotD.oughtto•3.Peter_____comewithustonight,butheisn’tverysure.A.mustB.mayC.canD.will4.–What____itbe?--It______beamailbox,foritismoving.It______beacar.A.can;can’t;mustB.can;can;mustC.can;mustn’t;mustD.must;mustn’t;can5.–Look,someoneiscoming.Guess__________.--Jack.He’salwaysontime.A.whocanitbeB.whohemayC.whohecanbeD.whoitcanbe6.–IsawMaryinthelibraryyesterday.--You_____her.Sheisstillabroad.A.mustn’tseeB.can’thaveseenC.mustn’thaveseenD.couldn’tsee7.David,you_____playwiththevaluablebottle,you_______breakit.A.won’t;can’tB.mustn’t;mayC.shouldn’t;mustD.can’t;shouldn’t•8.SusanrefusestomarryJacknow.She______hermind.A.mustchangeB.shouldhavechangedC.musthavechangedD.wouldhavechanged9.Sue________cometogetherwithustonight,butsheisn’tverysureyet.A.mustB.mayC.needD.will•10.AuntMargaret_________thetrain,otherwiseshewouldhavearrivedherebynow.A.musthavemissedB.shouldhavemissedC.hadmissedD.mightmiss典型错误1.Hemustn’tbeintheclassroom.()can’t2.Youmightleavethebagonthebed.()mighthaveleft3.Youmusthaveseenthefilmlastweek,have’tyou?()didn’tyou4.LiMingmusthavebeentoJapan,didn’the?()hasn’the情态动词+have+done”表“本来…”使用情形分析一、shouldhavedone过去本来应该（而实际上并没有…)shouldnothavedone本不应该…而实际上却已经…”如：1、Weshouldhavestudiedlastnight,butwewenttotheconcertinstead.我们昨晚本应学习的，但我们却去看音乐会了。（实际上没有学习）★二、couldhavedone它表示过去本来能够…实际上没能做…。如1、Icouldhaverun100metresin12seconds.我本来能用12秒钟完100米的.（实际上没能）2、Ifyoucouldhavefinishedthetaskintime，youcouldhavebeenpromoted.如果你当时能如期完成那任务的话，你可能已提升了（实际上没有被提升）三、neednothavedone它表示过去已做的事，事实上没有必要。如，1、Ineednothavegotupsoearly.我本来不必要那么早起床的（事实上早已起床）2、Ineednothavewaitedforthetrainforanhour.我本来不必要等一个小时的火车。（事实上已经等了一个小时）问题:wouldhavedone在什么情况下使用呢?四、wouldhavedone用在虚拟语气中表示与过去事实相反之假设的结果，常与if的条件句连用。1、IwouldhavehelpedyouifIhadknownofyourdifficulties.要是我当时知道你们的窘境，我就会帮助你了（而实际上没有帮助你）2、Ifithadn‘trainedyesterday,wewouldhavegoneoutforawalk.假如昨天没下雨，我们就去散步了。（实际上没有去）。Practice1.MrWhite____at8:30forthemeeting,buthedidn’tturnup.A.shouldhavearrivedB.shouldarriveC.shouldhavehadarrivedD.shouldbearriving2.Ifhehadbeenhereyesterday,he______thispopstar.A.wouldmeetB.wouldhavemetC.metD.musthavemet3.ItishardformetoimaginewhatIwouldbedoingtodayifI____inloveattheageofsevenwiththeMelindaCoxLibraryinmyhometown.A.wouldn’thavefallenB.hadnotfallenC.shouldfallD.weretofallbye-bye