2023学年完整公开课版米占东直播228

米占东名师网络工作室直播课堂UNIT2HealthyEatingDiscoveringusefulstructures主讲：米占东GrammarandUsage情态动词对过去推测用法

理解推测推测肯定mustcouldmaymightcannot

couldnotmaynotmightnot肯定句否定句/疑问句havebeen+表语（状态）havedone（动作）havebeen+表语（状态）havedone（动作）must不用在否定或疑问句中，can不用在肯定句中说出下列结构的含义musthavedonecould/may/mighthavedonecan'thavedonecould/may/mightnot+havedonecan/could/mighthavesbdone(≠May…havedone?)过去肯定做过某事过去不可能做过某事过去也许做过某事（肯定句）过去做过某事吗？(疑问句）过去可能没有做过某事

“must+have+done”

表示对过去事情的肯定推测，译成“过去一定做过某事”，该结构只用于肯定句。1.Itmusthaverainedlastnight,forthegroundiswet.昨晚一定下雨了，因为地面还是湿的。

2.Youmusthavebeenmadtospeaktotheservant.

你和仆人说话，一定是发疯了。

“couldhavedone”1)表示猜测，“过去可能做过某事”,多用于疑问句；2)用于虚拟语气，意思是“本来能够做某事而没有做”。Whatcouldhavehappened?难道可能发生了什么事吗？Thisglassiscracked.Someonecouldhavedroppedit.

这个玻璃杯破了。可能是谁把它掉在地上了。

Hecouldhavepassedtheexam,buthewastoocareless.本来他能够通过考试，但是他太粗心。“mayhavedone”

表示对发生过的事情的推测，意思是“可能已经”或“也许已经”，用于肯定句中。—WhathashappenedtoGeorge?—Idon'tknow.Hemayhavegotlost.—乔治发生了什么事？——我不知道，他可能迷路了。

“mighthavedone”

1)表示对过去事情的推测，might与may意思相同，但可能性更小。1.Hemighthavegivenyoumorehelp,eventhoughhewasbusy.他或许会多给你一些帮助，即使他很忙。Hecan’t/couldn’t/maynot/mightnothavegoneoutbecausethelight’son.

(现在对过去的推测)Ithoughthecouldn’t/mightnothavegoneoutbecausethelightwason.

(过去对过去之前的推测)

学习理解can/could/may/mightnot+havedone二、“can’thavedone”

“couldn’thavedone”

不可能做过某事表示对过去事情的否定推测，“couldn’thavedone”较少使用。1.Mr.Smithcan’thavegonetoBeijing,forIsawhiminthelibraryjustnow.史密斯先生不可能去北京了，我刚才还在图书馆见过他。2.Marycan'thavestolenyourmoney.Shehasgonehome.玛丽不可能偷你的钱，她回家去了。“can…havedone”

表示对发生过的事情的推测，用于疑问句中。It`ssolate.Wherecanshehavegone?天晚了，她可能去哪儿了呢？

“couldhavedone”1)表示猜测，“过去可能做过某事”,多用于疑问句；Whatcouldhavehappened?难道可能发生了什么事吗？Thisglassiscracked.Someonecouldhavedroppedit.

这个玻璃杯破了。可能是谁把它掉在地上了。

小综合练习1. —IthinkHelenisathome.

—No,she_____be,forshephonedmefromtheairportjustfiveminutesago. A.mustn’t B.needn’t C.can’t D.oughtnot2.-Goodmorning.IgotanappointmentwithMissSmithyesterday.-Ah,you______beMr.Peter.A.mightB.mustC.wouldD.can7. —Thereisnolightintheroom.

—_____hebesleeping? A.Must B.Shall C.Can D.Will8.Hurryup,he_____foryouattheschoolgatenow. A.maybewaiting B.mayhavewaited C.mustbewaiting D.mightwait9.Thiscakeisverysweet.You______alotofsugarinit.

A.shouldput

B.couldhaveput

C.mightput

D.musthaveput

10.——Ileftmyhandbagonthetrain,but

luckilysomeonegaveittoarailwayofficial.

——Howunbelievabletogetitback!Imean,someone______it.

A.maysteal

B.mighthavestolen

C.muststeal

D.musthavestolen11.-Shelooksveryhappy.She__havepassedtheexam.-Iguessso.It’snotdifficultafterall.A.shouldB.couldC.mustD.might12.She___haveleftschool,forherbikeisstillhere.A.can’tB.wouldn’tC.shouldn’tD.needn’t11.-Shelooksveryhappy.She__havepassedtheexam.-Iguessso.It’snotdifficultafterall.A.shouldB.couldC.mustD.might12.She___haveleftschool,forherbikeisstillhere.A.can’tB.wouldn’tC.shouldn’tD.needn’t5.Michael____beapoliceman,forhe’smuchtooshort.A.needn’tB.can’tC.shouldD.may6.----IstayedatahotelwhileinNewYork.----Oh,didyou?You____withBarbara.A.couldhavestayedB.couldstayC.wouldstayD.musthavestayed7.MysistermethimattheGrandTheateryesterdayafternoon,sohe____yourlecture.A.couldn’thaveattendedB.needn’thaveattendedC.mustn’thaveattendedD.shouldn’thaveattendedBAA总结“情态动词+完成式”

must/could/may/might+havedonecan'tcould/may/mightnot+havedonecan/could/might+havesb.done?should(oughtto)havedoneshouldn't(oughtn'ttohavedone