译林牛津模块四Unit2grammar

情态动词Modal

verbsModalverbs第一章单击此处添加标题Howmanypairsofmodalverbs?Weusemodalverbstotalkabout:

ability能力obligation责任、义务certainty确定permission允许Wealsousemodalverbsto:makerequest提出请求makesuggestions提出建议makeoffers提供帮忙giveadvice提出忠告Modalverbs情态动词没有人称和数的变化，有词义，但是不完整，不能单独做谓语，必须和不带to的动词不定式连用。1.ability

can,could和beableto的用法

can表示与生俱来的能力或一种客观可能，could是其过去式我认为没有你的帮助他不能解决这个问题。Idon‘tthinkhe____________________withoutyourhelp.两年前Rose就能自己做饭了。Rose_______________forherselftwoyearsago.

cansolvetheproblemcouldcookmealscan,could和beableto的用法

beableto更加强调通过后天的学习和努力获得的能力，或者在某个客观的场合和背景下，能做到的事情。爱迪生总是好奇为什么母鸡可以孵小鸡，而他却不能。Edisonalwayswonderedwhyhens_______hatch(孵)chickenswhilehe________________.

could

wasnotabletocan表示与生俱来的能力或一种客观可能，could是其过去式1.abilityNow,manyofuscanspeakEnglishquitewell,butafewyearsago,wecouldn't.Howaboutinthefuture?Inthefuture,wewill/shallbeableto....beableto有无时态变化?Exercise:can/beabletoAbigfirebrokeoutinABChotelyesterday.Luckily,everyone__________runoutofthebuilding.wasableto2.She_____speakbothEnglishandFrench.can=managedtodo/succeededindoing

1.Amancanneverhavetoomanyfriends.2.你过马路的时候再小心也不为过。补充：can/could:cannever/can’t……too表示“无论怎样…也不过分”，“越…越好”。Youcan’tbetoocarefulwhilecrossingtheroad.

Amancanneverhavetoomanyties.Andawomancan'thavetoomanyhats.oughttoshouldYououghttobekindtoyourfriends.---Oughtyoutobekindtotheenemy?---IthinkIoughtnotto.2.obligationoughttoshouldoughtto与should意思接近，大多数情况下二者可以互换，但是should

主观看法,用于各种人称。oughtto

客观情况，在谈到法律、义务和规定时使用。1.Weshould／oughttohelpeachotherandlearnfromeachotherinourwork．2.Theyshouldnotallowcarstoparkhere;thestreetisnotwideenough.3.Sheisyourmother,soyououghttosupporther．4.Oughthetogo?Yes,Ithinkheought(to).2.obligation2.obligationmust与haveto都可以表示“必须”的意思，但要注意以下两点区别。

1)must只有现在时，而haveto有现在时、过去时和将来时。如：2)must表示主观看法，haveto则侧重于客观需要。如：

·Wemustworkhard,orwe'llfailintheexams．

·Twoyearsago,thepoorgirlhadtoleaveschoolforlackofmoney．

Wemustbestrictwithourselvesineverything．Incitieswithmanycars,somepeoplehavetowearmasks．

mustadvisabilitynecessityhavetooughtto/shouldYourmotherbringsyouupandtakesgoodcareofyou,sowhensheisold,you___lookafterherinreturn.

A.canB.mayC.havetoD.must

2.obligationDmust表示肯定的猜测，译为“一定”，不能用于否定句或疑问句。Thismustbeyourpen.Hemustbedoinghishomeworknow.Hemusthaveseenthefilm.Hemusthaveseenthefilmlastweek.must2.表示“坚持”（常用于固定句型：ifyoumustdosth.如果你非得要做某事）如果说你真的要走，把我的相片还给我。Ifyoumustleave,pleasereturnmyphoto.,didn'the?,haven'the?,isn'the?,isn'tit?Imight/may/could/should/oughtto/will/must

watchtheTVprogrammethisweekend.3.certaintymight/may/could/should/oughtto/will/mustveryuncertaintyalmostcertaintyHeisathome.(事实)Hemustbeathome.(非常肯定地判断)Heoughttobeathome.(很可能)Hecould

beathome.(很可能)Hemaybeathome.(仅仅可能而已)Hemightbeathome.(或许，非常不确定)Hecouldn'tbeathome.(很可能不在家)Hecan'tbeathome.(一定不在家)Heisn'tathome.(事实)ExerciseHe_____beathome,forhejustcalledmefromhishome15secondsago.A.mayB.mightC.must

D.couldCMayIcomein?

允许，许可4.permissioncan/could/may/might could比can更委婉，might比may更委婉—CanIwatchtheOlympics?—Yes,youcan./No,youcan’t.—MayIwatchTVafterfinishingmyhomework?—Yes,youmay.//No,youmaynot.

No,youmustn’t./No,you’dbetternot.

4.permissioninformal/spokenformal/written允许，许可祝你成功！

Mayyoubehappyallyourlife.

may用于祈使句中表示祝愿。Mayyousucceed.

P28READPART1&2

1.Will/Canyoureadthesentenceoncemore?提出请求给出忠告提供帮忙提出建议3.Shallwewatchafilmtonight?2.Iwillhelpyouifyouhaveanyproblems.4.Themanagerisnotinnow.Youshouldcomebackatthreeo’clock.Can

youhelpmewiththecoronovirus?5.Makingrequests(提出要求):Ihavesometroubleinthemedicalequipment.willcancouldwouldinformalformalwill/would:Attention:Iwillgototheparkwithyoutomorrowifyouwilloffermelunch.

Question:Isthissentencecorrect?Why?情态动词表示“意愿”will表示意志、愿望和决心。

Iwillneverdothatagain.

Shallweinjectdisinfectantintothepaitents?6.Makingsuggestions(提出建议):Thedisinfectant(消毒剂)

cankillthevirusinoneminute.6.makesuggestions1.shall常用于第一，三人称疑问句中，表示征求对方意见。—Shallwe/I/he/she/theygobacktoschool?—Yes.—Shallhecomein?—Ok.shall:2.Shall用于第二、第三人称，表示说话人给对方命令、警告、允诺或威胁。

Youshallgetcontracted(感染)ifyoudon’twearafacemask.

Heshallgohomeafter14-dayquarantine.Heshallbepunishedifhebreaksthelaw.隔离quarantine7.Makingoffers(提供帮助):Don’tworry,dearfriend.Wewillhelpyououtwiththemedicalcarepersonnel.Serbia7.makeoffers

willshallI'llwashyoursportsjacket.ShallIgetaticketforyou?Shallwecarrythebooksforyou?ShallIcleantheblackboardforyou?will/would:8.giveadviceshould/oughttoYoushouldnot/oughtnottoeatporridgeinthemorning.Thestudentsshould

haveeggsandmilkforbreakfast.

1.Hemay/mightcometomorrow.2.Hemay/mightknowit.3.Hemay/might

bewaitingforyounow.4.Hemay/might

bewaitingforyouhenyougetthere.5.Hemighthaveseenthefilmyesterday.6.Hemay/might

havearrivedinBeijingbynow.7.Hemighthavebeenwaitingforyouwhenyouphonedhim.将来现在

情态动词+V原

情态动词+be+V-ing过去进行现在完成进行现在进行将来进行

过去现在完成情态动词+havedone情态动词+havebeendoing情态动词表推测MoreexamplesTheboysmaybeplayingfootballontheplayground.Theboysmayhavefinishedtheirhomeworkbythetimeschoolisover.Heplaysbasketballverywell.Hemusthavepracticeditalot.OurheadmastermusthavebeentotheUSA,forheknowsthecountrysomuch.He_____________________(catch)theearlybus;buthewasdelayedbyhelpingastranger.You_____________________(phone)me,thoughyouwerebusythen.Someone____________________(open)thecage—thelioncouldn'thaveescapedonitsown.---Wasthatthemanagerwhowalkedby?---No,it_________________(be).HehasgonetoFranceonbusiness.5.Theplant'sdead.MaybeI_________________________

(give)itmorewater.IknowI___________________________

(take)themoney.You___________________________(do)that;Ihadwarnedyouofthatseveraltimes.Therewasplentyoftime.I______________________(hurry).I_____________________(help)you,butIwastoobusy.could/might/must/should/oughtto/need/would+havedone

couldhavecaughtmighthavephonedmusthaveopened

can'thavebeen

shouldhavegivenoughtnottohavetakenshouldn'thavedoneneedn'thavehurriedwouldhavehelped情态动词+havedonecouldhavedone本可能（却没有）mighthavedone本可以做（却没有），“委婉责备”must

havedone“肯定/一定做了或发生了某事”，只用于肯定句；其否定形式can't/couldn'thavedone“不可能，肯定不会”should/oughtto+havedone本该做（而没做）

shouldn't/oughtn'tto+havedone本不该做（却做了）needn'thavedone本不需要做某事而实际上做了would/wouldn'thavedone本想做某事而没做/本不想做某事而做了Haveatry!

1.Aleft-luggageofficeisaplacewherebags____beleftforashorttime,especiallyatarailwaystation.

A.shouldB.canC.mustD.will2.How___yousaythatyoureallyunderstandthewholestoryifyouhavecoveredonlypartofthearticle?

A.canB.mustC.needD.mayBA允许能力3.—Theroomissodirty.____wecleanit?—Ofcourse.A.WillB.ShallC.WouldD.Do4.MyEnglish-Chinesedictionaryhasdisappeared.Who___havetakenit?A.shouldB.mustC.couldD.wouldBC建议推测，“可能”用于疑问句或否定句5.—Ihearyou'vegotasetofvaluableAustraliancoins.___Ihavealook?—Yes,certainly.A.DoB.MayC.ShallD.Should6.Iwasreallyanxiousaboutyou.You___homewithoutaword.A.mustn'tleaveB.shouldn'thaveleftC.couldn'thaveleftD.needn'tleaveBB允许本不该做某事（而做了）7.—AreyoucomingtoJeff'sparty?—I'mnotsure.I__gototheconcertinstead.A.mustB.wouldC.shouldD.might8.Sorry,I'mlate.I____haveturnedoffthealarmclockandgonebacktosleepagain.A.mightB.shouldC.canD.willDA确定“可能”对过去动作的猜测“可能”9.—WhencanIcomeforthephotos?Ineedthemtomorrowafternoon.—They___bereadyby12:00.A.canB.shouldC.mightD.need10.Thefirespreadthroughthehotelveryquicklybuteveryone____getout.A.hadtoB.wouldC.wasabletoD.couldBC确定“应该”能力；经过努力后Thanks

1.could/mighthavedone

couldhavedone

本可能（却没有）他本能够赶上早班车；他是因为帮一个陌生人而晚点的。Hecouldhavecaughttheearlybus;buthewasdelayedbyhelpingastranger.

mighthavedone

本可以做（却没有），“委婉责备”

你再忙也该给我打个电话。Youmighthavephonedme,thoughyouwerebusythen.2.musthavedone表示对过去所发生的事情表示推测，表示“肯定/一定做了或发生了某事”，只用于肯定句，其否定形式是Someonemusthaveopened

thecage—thelioncouldn'thaveescapedtonitsown.Ididn'thearthephone.Imusthavebeenasleep.can