情态动词的用法及专项练习

1情态动词的用法一．分类：1.只做情态动词：can（could）、may（might）、must....后接动词原形。2.可做情态动词又可做实义动词。如：need，dare3.具有情态动词特征：have（has，had）to，usedto（过去常常）。二．情态动词的用法：情态动词后接动词原形1.must的用法1）must意为“必须；应该；一定”。表示说话人的主观意志，表示必须要做的。如：Wemustfinishreadingthebookintwoweeks.我们必须在两周内看完这本书。2）表示说话人对事物的推测，语气比may肯定，只用于肯定句中。Mustbe译为“一定是”如：Mr.Liumustbeintheoffice.刘老师一定在办公室。3）用must提问时，如果是否定回答，多用needn’t或don’thaveto，表示“不必，没必要”，而mustn’t表示“绝对不行，不可以，禁止”的意思。如：---MustIfinishmyhomeworknow?---Yes,youmust.---No,youneedn’t/don’thaveto4）haveto意为“必须；不得不”，有人称、时态和数的变化，后跟动词原形，表示客观需要。如：WhenIwasyourage，Ialreadyhadtowork.2.can的用法：1）can意为“能；会；可以”。表示能力，其否定式是cannot=can’t。如：Shecansing.她会唱歌。2）表示请求许可。CanI...?意思是“我可以……吗？”，较口语化。3）can的过去式是could，如：Lucycouldswimattheageoffive.露西五岁时就会游泳了。could也可表示较can更为委婉的语气。如：Couldyouhelpme?帮帮我好吗？4）can表示推测时，常用于否定句和疑问句中。Can’tbe“不可能是”，若是疑问句，其肯定回答用may或must。如：—Wherecanitbe?它会在哪里呢？—Itmay/mustbeinyourdesk.它可能/一定在你的课桌里。否定回答：Itcan’tbeinyourdesk.它不可能在你的课桌上。3.may的用法：1）may意为“可以；可能”。表示请求、许可。如：MayIlookatyourCDplayer?我可以看一下你的CD机吗？2）表示可能性（说话人的猜测），常用于肯定句中。如：Yoursistermaybewaitingforyounow.你妹妹可能现在正在等你呢。3）以may引起的一般疑问句，否定回答多用mustn’t；—MayIcomein?我可以进来吗？—No,youmustn’t.不，不行。4.need的用法：1)need作情态动词时，意为“需要”，后接动词原形，常用于疑问句和否定句中，否定形式：needn’t,疑问句：Need提前如：Youneedn’ttrytoexplain.NeedIexplainit?2)need作为实义动词时，后接动词不定式todo，有人称和数的变化。如：Sheneedstocometomorrow.He(不需要）borrowmoney.Dothey______________(需要）dohomeworktoday？25.hadbetter的用法：hadbetter（not）dosth最好（不要）做某事如：You’dbetter_______(stay)athome.You’dbetter__________(notwatch)TV.练习：()1John___cometoseeustonight,butheisn'tverysureyet.A.mayB.canC.hastoD.must()2They___dowellintheexam.A.canbeabletoB.beabletoC.canabletoD.areableto()3-MayItakethisbookout?-No,you___.A.can'tB.maynotC.needn'tD.aren't()4You___goandseeadoctoratoncebecauseyou'regotafever.A.canB.mustC.dareD.would()5-CanyouspeakJapanese?-No,I____.A.mustn'tB.can'tC.needn'tD.maynot()1-He___beintheclassroom,Ithink.-No,he___beintheclassroom.Isawhimgohomeaminuteago.A.can;maynotB.must;maynotC.may;can'tD.may;mustn't()2-ShallIgetonemorecakeforyou,Dad?-Thanks,butyou___,I'vehadenough.A.maynotB.mustnotC.can'tD.needn't()3Eventhetopstudentsinourclasscan'tworkoutthisproblem,soitbeverydifficult.A.mayB.mustC.canD.need()4Heisn'tatschool.Ithinkhe___beill.A.canB.shallC.mustD.hasto()5___Itakethisone?A.MayB.WillC.AreD.Do()1Thechildren___playfootballontheroad.A.can'tB.canC.mustn'tD.must()2You___belateforschoolagainnexttime.A.mustn'tB.needn'tC.don'thavetoD.don'tneedto()3-MustIdomyhomeworkatonce?-No,you___.A.needn'tB.mustn'tC.can'tD.maynot()1Hisarmisallright.He___goandseethedoctor.A.hasnottoB.don'thavetoC.haven'ttoD.doesn'thaveto()2Hehadtogiveuptheplan,___he?A.didB.didn'tC.doesD.doesn't()3Theyhadtowalkhere,___they?A.mustn'tB.didC.didn'tD.hadn't()1Hehadbetterstayhere,___he?A.didn'tB.don'tC.hadn'tD.isn't()2You'dbetter___latenexttime.A.nottobeB.notbeC.won'tbeD.don'tbe()3You'dbetter___yourhair___onceamonth.A.had;cutB.had;cuttedC.have;cutD.have;cutted()4You___askthatmanoverthere.Maybeheknowstheway.A.hadbetternottoB.hadnotbetterC.hadbetterD.hadbetternot()1-ShallwegoandvisittheHistoryMuseumnextSunday?A.HereyouareB.Sorry,Ican'tC.Yes,pleaseD.Letmetry3()2-Whydon'tyouaskMiketogowithus?-Thanks,___.A.IwillB.Iwon'tC.leanD.Imay()3-___Itakethenewspaperaway?-No,youmustn't.You____readitonlyhere.A.Must;canB.May;canC.Need;mustD.Must;must()1Excuseme.___youpleasepassmethatcup?A.DoB.ShouldC.WouldD.Must()2___youliketohaveanothertry?A.CouldB.WillC.WouldD.Do()3-Wouldyouliketogoboatingwithus?-Yes,___.A.I'dlikeB.IwantC.I'dliketoD.Ido()1You___worryaboutyourson.Hewillgetwellsoon.A.needn'tB.can'tC.mustn'tD.haveto()2Thepoormanneedsourhelp,___he?A.needB.needn'tC.doesD.doesn't()3-Mustwedoourhomeworkfirst?-No,you___.Youmayhavearestfirst.A.mustn'tB.needn'tC.maynotD.can't参考答案：1.1-5ADABB2.1-5CDBCA3.1-3CAA4.1-3DBC5.1-4CBCC6.1-3BAB7.1-3CCC8.1-3ADB