情态动词表推测的讲解及练习题

优胜教育1表推测时，英语中只使用must,may,might,maynot和can't。这五个表达的语气依次递减：must:一定（语气肯定）may：也许（不很肯定）might：或许（比may语气更弱）maynot：也许不（表否定）can't：一定不（must的反义）推测现在的事情用must,may,might,maynot和can't+do或bee.g.Shemustbeathomenow.Theboymayplaynow.推测过去的事情用must,may,might,maynot和can't+havedonee.g.Shemighthavebeenillyesterday.Hemusthaveholdtheparty.情态动词must,can,could,may,might表推测的用法情态动词中的must,can,could,may,might都表推测。其中must的可能性最大，can/could次之，may/might最小。具体用法如下：1.must的用法（1）表示推测“可能性”时，意思是“一定、准是”，语气较肯定，较有把握。HemustbeAmerican.=ItiscertainthatheisAmerican.他准是个美国人。（2）must表推测只能用于肯定句。如果要表示“一定不、肯定不”的意思时，应用can’t,如询问某种可能时，应用can。Hemustknowmyaddress.他肯定知道我的地址。（一定）Hecan’tknowmyaddress.他肯定不知道我的地址。（一定不）Canheknowmyaddress?他知道我的地址吗？（询问可能性）（3）must表示推测时，可以推测现在/正在发生的动作/过去发生的动作。Hemusthaveacarnow.（现在）他一定有辆小汽车。Hemustbedoinghisexercisesintheclassroom.（正在进行）他一定在教室里做练习。Hemusthavefinishedthework.（过去发生）他一定已完成了工作。注：must表示推测时很少用于将来的情况。一般不用Hemustcometomorrow.可用It`scertain/I’msurethathewillcometomorrow.（4）在反意疑问句中，当附属部分含有表示推测意义的must时，疑问部分的助动词应与must后面的动词在非推测情况下的用法保持一致。Hemustbeaworker,isn’the?（现在）他准是个工人，是吗？Itmusthaverainedlastnight,didn’tit?（过去）昨晚一定下雨了，是不是？YoumusthavelearnedEnglishformanyyears,haven’tyou?（完成时）你一定学了好多年英语，是吗？2.can/could的用法（1）can表示推测“可能性”时，往往用于否定句或疑问句。Can’t“一定不”，语气很肯定。can在疑问句中意思是“会、可能”。用于肯定句时，表示理论上的，优胜教育2潜在的可能性（有倾向，实际上未必会发生或者不涉及实际是否发生）往往与sometimes或者someone有关。Accidentscanhappen.Hecan’tbeathome.=Itisimpossiblethatheisathome.他一定不在家。（2）can/can’t后可接进行时/完成时，表示对现在发生的动作或过去发生的动作进行推测。Theycan’tbereadinginthelibrary.他们一定不在图书馆读书。Hecan’thavegonetoShanghaiforIsawhimaminuteago.他不可能去了上海，我刚才还看见他。It’ssolate.Wherecanshehavegone?天晚了，她可能去哪儿了呢？（3）在反意疑问句中，当陈述部分含有表示推测意义的can’t时，疑问部分的助动词应与can’t后面的动词在非推测情况下的用法保持一致.Hecan’tbeateacher,ishe?他不是教师，是吗？Shecan’thavefinishedherhomework,hasshe?她一定没有完成家庭作业，是不是？could可用于表示某事有可能发生表示可能性不大的推测。意思相当于may/mightDon’teatit.Itcouldbepoisonous.不要吃它，可能有毒。Theplanecouldbedelayedbyfog.飞机可能会因为雾晚点。（5）could还可以用于表示客气、委婉、礼貌的请求语气。Excuseme,couldyoutellmethewaytothebusstation?Couldyouhelpme?（6）couldn’t表示否定推测，表示某事不可能真实，或由于特定事实或环境某事肯定不会发生。Itcouldn’tpossiblybepoison.这不可能是毒药。表示对过去发生的事推测，常常和havedone连用Hewasnotathomelastnight.Hecould/mighthavegonetomovies.Ididn'tseeheratthemeetingyesterday;shecouldn'thavespokenatthemeeting.3.may和might的用法（1）may,might表示推测“可能性”时，意思是“可能”、“也许”，语气没有must肯定。Hemay/mightbeAmerican.=ItispossiblethatheisAmerican.他可能是个美国人。注：might不表示过去时态，只是语气上比may更委婉，表示的可能性更小。（2）may,might表推测时，可以用于否定句，意思是“可能不、也许不”，但不用于疑问句。Hemay/mightnotbeathome.他也许不在家。（3）may,might可以推测现在正在发生的动作或过去发生的动作。Hemay/mightbesleepingnow.（现在）他可能正在睡觉。优胜教育3Theboymay/mightnotbewatchingTVathome.（现在）这个男孩可能没在家看电视Thesestudentsmay/mighthaveseenthefilmbefore.（过去）这些学生以前可能看过这部电影。（4）may,might还可以推测将来的情况。Ithinkweshouldtakeraincoatwithus,itmayrain.我想我们应该带上雨衣，可能要下雨了。Shemightnotcomethisafternoon.她今天下午可能不来一、单项选择1John___cometoseeustonight,butheisn'tverysureyet.A.mayB.needC.can’tD.must2Johnisn’tintheclassroom.HeplaysoccerontheplaygroundwithBob.A.canB.mustC.shouldD.can’t3That_______notbeherhusband.Sheisstillsingle.A.mayB.canC.couldD.might4You___goandseeadoctoratoncebecauseyougotafever.A.canB.mustC.dareD.would5-CanyouspeakJapanese?-No,I____.A.mustn'tB.can'tC.needn'tD.maynot6-He___beintheclassroom,Ithink.-No,he___beintheclassroom.Isawhimgohomeaminuteago.can;maynotB.must;maynotC.may;can'tD.may;mustn't7-IsLenaswimminginthepool?-No,sheswim.Sheisterrifiedofwater.A.maynotB.mustnotC.can'tD.needn't8Heisn'tatschool.Ithinkhe___beill.A.canB.shallC.mustD.might9-Whatdoyouthink“upset”means?-I’mnotsure.Itmean“sad”.mayB.mustC.canD.should10Thechildren___playfootballontheroad.can'tB.canC.mustn'tD.must11.Theroadiswet.It______lastnight.AmustrainBmusthaverainedCcouldhaverainedDcanhaverained12.He______youmorehelp,eventhoughhewasbusy.AmighthavegivenBmightnotgive优胜教育4CmaynothavegivenDmaygive1.Look!Thelightisoutinherroom.She————tobedalready.A.mustgoB.hadtogoC.musthavegoneD.hasgone2.Wehadawonderfultimeyesterday.You————.Whydidn'tyoucome?A.hadtocomeB.shouldhavecomeC.mighthavecomeD.musthavecome3.─Therewerealreadyfivepeopleinthecarbuttheymanagedtotakemeaswell.─It______acomfortablejourney.A.can'tbeB.shouldn'tbeC.mustn'thavebeenD.couldn'thavebeen4.MysistermethimattheGrandTheatreyesterdayafternoon,sohe___yourlecture.A.couldn'thaveattendedB.needn'thaveattendedC.mustn'thaveattendedD.shouldn'thaveattended5.Iwasreallyanxiousaboutyou.You_____homewithoutaword.A.mustn'tleaveB.Shouldn'thaveleftC.Couldn'thaveleftD.needn'tleave6.Oh,I’mnotfeelingwellinthestomach,I_____somuchfriedchickenjustnow.A.shouldn’tcutB.mustn’thaveeatenC.shouldn’thaveeatenD.mustn’teat7.Mr.White_____at8:30forthemeeting,buthedidn’t’showup.A.shouldhavearrivedB.shouldarriveC.shouldhavehadarrivedD.shouldbearriving8.You______betired-you'veonlybeenworkingforanhour.A.mustnotB.won'tC.can'tD.maynot9.-Isn'tthatAnn'shusbandoverthere?-No,it_______behim-I'msurehedoesn'twearglasses.A.can'tB.mustnotC.won'tD.maynot10.There____beanydifficultyaboutpassingtheroadtestsinceyouhavepractisedalotinthedrivingschool.A.mustn’tB.shan’tC.shouldn’tD.needn’t11.Iwasonthehighwaywhenthiscarwentpastfollowedbyapolicecar.They______atlease150k