高中英语公开课庐江二中黄淑萍2013.10情态动词有一定的意义，但没有人称和数的变化，不能独立使用，它和后面的动词构成谓语．1.must1)表示义务或强烈的劝告，意为“必须”“应该”，其否定式表示“不应该”“不许可”“不准”“禁止”。1)Youmustfinishyourhomeworkfirst.2)Childrenmustn’tspeaklikethattotheirparents.2)表示“非要，偏要，”表达说话者的不满，3)Whymustyoubetalkingsoloudlywhenothersaresleeping?3)表示对具体事情的推测，意思是“一定，肯定”语气较强，只用于肯定句中。1)HemustcomefromAmerican.2)Hemustbesleepingatthemoment.3)Hemusthavestayeduplastnight.1.Judgingfromhisaccent,hemustbefromthesouth,2.Tomboughtalotofapples.Hemustlikeeatingapples,3.Itiseleveno’clockatnightandthelightsareoff.Theymustbesleepingnow,isn’t,he?doesn’the?aren’tthey?1.Wemusthavelearned2,000wordsbytheendoflastterm,hadn’twe?3.HemusthavegonetoBeijing,didn’tit?hasn’the?2.Itmusthaverainedlastnight,fortheroadwasverymuddy，注意：must和haveto1.must用于一般问句中,肯定回答用must否定式用needn’t或don’thaveto，做“不必”,mustn’t表示“禁止，不允许”e.g.MustIfinishallassignmentsatatime?Yes,youmust.No,youneedn't./don’thaveto.Idon’tlikethisTVset.Wemustbuyanewone.Therewasnomorebus.Theyhadtowalkhome.2.must着重说明主观看法，haveto强调客观需要。另外，haveto能用于更多时态。1)Someofuscanusethecomputernow,butwecouldn’tlastyear.2)Thenew-builttheatrecanseat1500people.3)Canshebeinthecomputercenter?4)Ithoughwhathesaidcouldnotbetrue.5)Can/CouldIuseyourdictionary?6)Couldyoulendmeahand?1)表能力3)表示“请求”“允许”(表请求时，口语中常用could代替can使语气更委婉，回答时用can)2)表示推测，意为“可能”“或许”，用于疑问句或否定句表示不可能2.can与could4)表示“许可”，可与may换用。7）Youcangohomenow.5)用于疑问句或否定句中时，表惊异、不相信等，意思是“可能、能够”。8）Howcanyousaythatyoureallyunderstandthewholestoryifyouhavecoveredonlypartofthearticle?I’msotiredthatIcan’thelpfinishtheproject.Hecan’thelpburstingoutlaughing.1)can’thelpdoing/todo/do情不自禁做什么/不能帮忙做什么2)can’ttooadj/advcan’tadj/advenough再怎样都不过分Youcanneverbetoocarefulwhendrivingacar.3)can’tbutdo/can’thelpbutdo/can’tchoosebutdo只能做什么Ican’tbutwaitforhimpatiently.固定词组注意1：Can和beableto区分Shecan/beabletosingthesonginEnglish.Thismachinecanmakeyoufeelcomfortable.1）can,beableto都可表示“能力”Can的主语是人或物,beableto的主语是人We’llbeabletofinishtheworksoon.Ihaven’tbeenabletoseethefilm.2）can只用于现在时和过去时(could)。beableto可以用于各种时态。3）表示特定的某一过去能力或表示成功地做了某事时，只能用was/wereableto，不能用could。HewasabletoescapefromEuropebeforethewarbrokeout.Hewasabletoswimbeforehegottired.注意2.can/couldhavedoneCan’t/couldn’thavedone对过去发生行为的可能性进行推测:Isawhimjustnowsohecouldn’thavegoneabroad.Wecouldhavefacedthedifficultytogether,butwhydidn’tyoutellme?1.Michael____beapoliceman,forhe’smuchtooshort.A.needn’tB.can’tC.shouldD.may2.Mr.Bushisontimeforeverything.How____itbethathewaslatefortheopeningceremony?A.canB.shouldC.mayD.must3.----IstayedatahotelwhileinNewYork.----Oh,didyou?You____withBarbara.A.couldhavestayedB.couldstayC.wouldstayD.musthavestayed4.MysistermethimattheGrandTheateryesterdayafternoon,sohe____yourlecture.A.couldn’thaveattendedB.needn’thaveattendedC.mustn’thaveattendedD.shouldn’thaveattendedBAAA3.may与might1)表示“许可”或“请求”，有“可以”的意思，口语中常用might代may,表示委婉语气。否定回答时...
