外研八下U4 情态动词（推测）核心语法精练（学生版）

Unit4Helpingout·表示可能性与推测的情态动词（学生考点概览·知识回顾2.否定推测：表示“不可能”用can2.否定推测：表示“不可能”用can't；表示“可能不”用maynot/might一、表示推测的情态动词概述情态动词可以表示说话人对某件事情的推测、判断。根据把握程度的不同，可以分1.肯定推测：表示把握很大时用must（一定，肯定）；表示可能性时用may/might（可能，也许）。3.疑问推测：表示“可能吗？”用can/could（could语气更委婉）。二、must表示推测must表示有把握的肯定推测，意为“一定，肯定”，通常只用于肯定句。表示对现在情况的推测，后接动词原形；表示对过去情况的推测，后接havedone。例：Youmustbetiredafterthelongwork.长时间工作之后，你一定累了。例：Thelightsareon.Hemustbeathome.灯亮着，他一定在家。三、can/could表示推测can/could表示推测时，常用于否定句和疑问句。can't表示“不可能”，语气很肯定；could表示可能性更弱。用于疑问句时，can比could可能性更大。例：Itcan'tbeDavidbecausehehasgonetoBeijing.不可能是David，因为他去北京了。例：Canthisbetrue?这有可能是真的吗？四、may/might表示推测may/might表示可能性，意为“可能，也许”。might不是may的过去式，而是表示可能性更小。may不用于一般疑问句表示推测，可用于否定句（maynot）。例：Hemaynotknowtheanswer.他可能不知道答案。例：Mikemightphone.Ifhedoes,couldyouaskhimtoringlater?Mike或许会打电话。如果他打电话，你能否让他晚点再打过来？五、常用表示“可能”的词语possible（形容词possibly/probably（副词maybe（副词）也可表示可例：Isitpossibletogetticketsforthegame?有可能弄到比赛的门票吗？例：Itwillpossibly/probablytakeusaboutaweek.我们可能需要一周左右。例：Maybeshewillcome.也许她会来。六、注意事项①表示推测的情态动词不用于将来时，表达将来的推测常用may/might/could。②must表示推测时，其否定式不是mustn't（mustn't表示“禁止”），而是③对正在发生的情况进行推测，用“情态动词+bedoing”。例：Shemustbewaitingforus.她一定在等我们。一、单项选择1．Usesunscreenwhenyou'reoutinthesun,oryourskin______getburned.A．mustB．mayC．shouldD．need2．---______Iparkmycarhereforawhile?---No,youmustn't.It'sano-parkingzone.A．WouldB．NeedC．MustD．May3．There______beafewshowersthisafternoon,sotakeanumbrellawithyou.A．can'tB．shouldC．mayD．mustn't4．---Dad,mayIgoouttoplayfootball?---No,you______.It'srainingheavilyoutside.A．can'tB．shouldn'tC．needn'tD．maynot5．---______Icomebackbeforesixo'clock?---No,you______.Butyou______bebacklaterthaneight.A．Must;needn't;can'tB．May;mustn't;can'tC．Can;can't;can'tD．Need;must;mustn't6．They______haveapicnicthisweekend,buttheyarenotsureabouttheweather.A．mustB．needn'tC．mightD．shouldn't7．---Whosejacketisthis?---It______belongtoTom.Look,hisnameisonA．canB．mightC．mustD．should8．Lisa______gotothemusicclubwithus,butshehasn'tdecidedyet.A．mustB．mightC．shouldn'tD．can't9．Weneverknowwhat______happeninthefuture,butwecanpreparefortheworst.A．mustB．mightC．shallD．should10．---I'vereceivedapackage.What'sinit?---I'mnotsure.It______beagiftfromyouraunt.A．mightB．mustC．shouldD．need11．---Ihaven'tseenMikefordays.---He'sjuststartedanewjob.I'msurehe______bebusy.A．canB．shouldC．mustD．may12．---Mom,canIplayoutside?---Yes,youcan.Butyou______bebackbeforedinner.A．canB．mayC．wouldD．mu13．13．---Look!There'sanotebook.---Oh,it______beLily's.Onlysheusesthiskindofnotebook.A．canB．mustC．mayD．might14．TheSmithshaveboughtalargehousewithagarden.It______beveryexpensive.15．Lookattheschoolrule.Itsayswe______belateforschool.A．canB．mustC．needn'tD．mustn't16．---Didyouhearwhathesaid?---He______bejoking---there'snowaythat'strue!A．canB．needC．mustD．should17．---Look!It______beMr.Li.---No,it______behim.HehasgonetoShanghai.A．may;mustn'tB．must;maynotC．must;can'tD．can;maynot18．---Myparentsarealwaysbusywithwork.SometimesIhavetocookmyself.---Oh,dear.You______becarefulwhencooking.19．---Look!Themanoverthereiswearingaredhat.IsheMr.Zhang?---It______behim.Mr.ZhanghasgonetoBeijingonbusiness.A．mustn'tB．can'tC．needn'tD．shouldn't20．---IsthisbikeLucy's?---Well,it______beLucy's.Hersisblue,butthisoneisred.A．can'tB．mustC．shouldD．needn't21．---______Icomebackbeforefiveo'clock?---No,you______.Butyou______bebacklaterthanseven.A．Must;needn't;needn'tB．May;mustn't;can'tC．Can;can't;can'tD．Must;needn't;can't22．---What'sthedateforthegraduationceremony?---It______beonJune25th.ButI'mnotsure.A．couldB．couldn'tC．mustD．mustn't23．We______getsomething______afterthemovie.I'mhungrynow.A．mightn't;toeatB．might;toeatC．couldn't;eatingD．could;eating24．---Listen!IsTomsingingintheclassroom?---It______behim.ButI'mnotsure.A．needB．couldC．mustD．would25．---Someoneisknockingatthedoor.IsitMary?---It______beher.Sheishavingameetingintheoffice.二、完成句子26．王老师不可能在办公室。我刚才在图书馆看见她了。26．王老师不可能在办公室。我刚才在图书馆看见她了。MissWang____________intheoffice.Ijustsawherinthelibrary.27．——请你帮我打扫一下房间好吗？——对不起，我不能。我必须写作业。---Couldyoupleasehelpmecleantheroom?---Sorry,I______.I______domyhomework.28．——请问我能用一下你的手机吗？——不，你不能。我正等着一个重要电话。---______Iuseyourphone?---No,you______.I'mwaitingforanimportantcall.29．你最好去看医生，可能需要拍个X光片。You'dbetterseeadoctor.You______needanX-ray.30．今天可能会下雨，因此我们最好早点出发。It______raintoday,sowe'dbetterleaveearly.31．他们现在可能在北京了。They______beinBeijingnow.32．这本书肯定很有趣。Thisbook______beveryinteresting.33．他肯定在家；灯是亮着的。He______beathome;thelightison.34．你一定是个医生，对吗？You______beadoctor,aren'tyou?35．这部电影一定很受欢迎。Thismovie______beverypopular.36．那个声音听起来可能是风声。Thatsound______bethewind.37．你不可能是认真的！You______beserious!38．他们可能已经离开了。They______haveleftalready.39．这一定是个误会。There______beamisunderstanding.40．她也许不知道这个秘密。She______notknowthesecret.一、语法填空阅读下面短文，在空白处填入1个适当的单词或括号内单词的正确形式。Inthepastfewyears,greatchangeshavetakenplaceinmyhometown.Theroads[1]______(use)tobenarrowandmuddy.Peoplelived[2]______oldandsmallhouses.Theairwasn'tfreshenough.Sometimes,terriblesmells[3]______(fill)thearea.Nowadays,wideandcleanroadsmaketravelingeasyforeveryone.Wecanchoose[4]______(difference)kindsoftransportationtogoanywhere.Thecity[5]______(build)lotsoftallbuildings.Sofar,mostof[6]______(we)havemovedintobigandmodernhouses.Theriverhasbecomemuch[7]______(clean)thanbefore,withclearwaterflowingthroughit.Theblueskyandwhitecloudscreate[8]______beautifulscene,andbirdssing[9]______(happy).Theenvironmentinmyhometownhasimprovedgreatly,[10]______westillneedtoworktogethertokeepitthisway.二、选词填空阅读短文，从方框中选择适当的词并用其正确形式填空，使短文通顺、意思完整。每空限填一词，每词限用一次。succeed,win,famous,skill,send,but,bad,spend,try,interestQuanQuanHongchan,ayounggirl,amazedthewholeworldattheTokyoOlympicGames.She[1]______thegoldmedalforthewomen's10-meterplatformdiving.Quanwasnotonlytheyoungestcompetitori