虚拟语气精讲精练及答案

1、虚拟语气总览英语中的三种语气英语共有三种语气，陈述语气、祈使语气和虚拟语气。陈述语气用来讲述事实，有肯定、否定、询问和感叹等形式，谓语动词有人称、时态和数的变化；祈使语气用于提出请求、建议、劝告、命令和警告等，以动词原形起句，否定式句前加Don；虚拟语气表示说话人所言内容不是事实，而是一种假设、愿望、建议、请求、命令或猜测，有时只是说话者的主观愿望，或表达他/她的强烈情感，谓语动词用特殊形式。非真实条件句的虚拟语气条件从句主句过去haddonewould/should/might/could/oughttohavedone现在did(be用were)would/should/might/cou

2、ld/oughttodo将来1、did2、shoulddo3、weretodowould/should/might/could/oughttodo巧计主句中五个虚拟引导词：MSCOW(奶牛女士)：might,should,could,oughtto,would2.1.与过去事实相反.IfIhadhadmuchmoneyatthattime,Iwould.haveboughtyouwhatyouwant.Ifyouhad.beenmorecareful,themistake.might.have.been.avoided.Ifyouhad.takenmyadvice,youwouldnt.hav

3、e.machuchamistake.Wewo.uldnt.have.succeededthad.notbeenfortheirhelp.Ifyouhad.beenhereyesterday,you.would.have.metthefilmstar.IfIhad.knownmoreaboutgivingfirstaid,Icould.have.helpedthem.Ifyouhad.got.upearlier,you.would.have.caughtthetrain.Ifwehad.hadenoughrainlastyear,we.could.have.gainedagoodharvest.

4、Ifyouhad.worked.alittleharder,you.could.have.passedthefinalexamination.Iftheyhad.invitedhertotheparty,she.would.have.attendedit.2.2与现在事实相反.IfIwereyou,Iwould.go.thereatonce.Ifmyclassmates.werehere,theywould.helpme.IfIwereyou,Iwould.acceptthejob.Ifclasses.weresmaller,childrenwould.learnmore.IfIwere,te

5、nyearsyounger,I.would.startalloveragain.IfIhad.enoughmoney,I.would.buyalargehouse.IfIhad.time,Iwould.go.shoppingwithyou.IfIknew.alltheanswerstoallyourquestions,I.would.beagenius.Ifhewereherenow,wewould,askhimaboutit.IfIhadtime,Iwould.study.French.IfIknewhernumber,Icould.ringher.可惜我不知道).Iftherewereno

6、gravity,weshould.notbe.able.towalk.(实际上地球引力始终存在。).IfIknew.theanswer,Iwould.tell.you.(实际上我确实不知道，所以肯定不能告诉你。).IfIhadmoneyonme,Iwould.lendyousome.We.would.not.be.able,towalkifthere.werenofriction.Ifyouwereinmyposition,whatwould.youdo?.Iftheytreatedmeasaslave,I.had.to.resign.Iftherewerenoexaminations,wes

7、hould.haveamuchhappiertime.Ifwisheswerehorses,beggars.mjght.ride.如果幻想能成为马匹，叫花子们都有了坐骑。).Lifemightbetoodullifithad.nodifficultiesinit.(倘若生活中没了困难，就会过于平淡。)与将来事实相反.Ifitrained/shouldrain/weretoraintomorrow,wewouldhavearest.Ifthesunwere.to.risefromthewest,I,would.marryyou.(注意：对将来虚拟的条件从句中，在实现的可能性方面过去式did最大，

8、shoulddo中等，weretodo最小。如本句太阳没有可能从西方升起，所以本句用wereto最恰当。).IfIwere.to.meethertomorrow,I.would.askheraboutit.Ifgreenplantsshould,.disappearsomeday,there.would.hardly.beanylifeontheearth.IfIwere.to.dothework,Iwould.do.itinadifferentway.Ifitshoul.d(were.to).rainthisafternoon,thefootballmatch.would.beputoff.

9、Ifyoumissedthefilmthisevening,youwould.besorryforit.(如果今晚错过了这场电影，你会遗憾的。实际上，你不会错过。).IfIwere.to.seehertomorrow,I.would.inviteherhome.Ifyoulived.thereforseveralmonths,youwould.change.yourmindabouttheplace.Ifthingswere.to.bedonetwice,allwould.be.wise.(如果事情能被做两次，人人都会变得明智。)混合型.Ifyouhad.followed,thedoctorv

10、scadyouwould.bemuchbetternow.(过去t现在).Ifyouhad.workedhard,youwould.beacollegestudentnow.过去t现在).Ifyouhad.listened,tome,youwouldnt.bieisuchtroublenow.过去现在).Ifyouhad.gotsixmorevotesyesterday,youwouldbeourchairmannow.(过去现在).IfIhad.earnedmuchmoneylastsummer,I.would.goonavacationnextmonth.(过去将来).Ifyouhesit

11、atedthismoment,you.m.ightsufferinfuture.现在将来)过去现在).IfIwere,you,Iwould.have.gonetoherbirthdayparty.现在过去).Ifithad.rainedlastnight,thegroundwould.bewetnow.过去现在).Ifyouhadnt,lentesomemoney,IcouldnhtenewhouseandmostlikelyIwouldn./t.bestilllivinginthedangeroushousenow.(过去过去现在)25.if的省略与条件句的倒装.Werel.you,丨wou

12、ld,have,.acceptedthejob.Wereshehere,shewouldsupportus.Wereyoutogofishingwithme,youwouldhaveamuchhappiertime.如果人人都是天使，政府就没有必要了。).Wereshemydaughter,wouldntalloertostudyabroad.Heearlier,you.would.have.metmygirlfriend.Had丄time,Ie.(本句中had是实意动词，而非主动词。).Had丄rmedearlier,Icould.have.done.somethingtopreventit

13、fromhappening.Manypersonsintheworlswould,.have,.succeeded.had.they,.not.wastedtheirvaluabletime.Should.it.befinetomorrow,we.would.goouting.Should.you.changeyourmind,noone.would,.blameyou.We.would.gonetoyourbirthdayparty.had.you.invitedus.13.Iwould.goshould.it.benecessary.Whatwould,.have,.happened.ha

14、d.Bob.waJkedfarther,asfarastheriverbank?.Had.it.not.been.foryou,Iwould.have.ostmyway.Were,.it.not.forwater,noplant.could.grow.(注：例句8、9知识点见“二6Ba”。).Bmon.people.or.high-ranking.officials,theystandequalbeforethelaw.(Whethertheybe).Be.the.weatherwhatit.may,Iwillleavetomorrow.(Whethertheweatherbewhatitma

15、y,)(注：例句13、14知识点见“八5”。)注意：在这一结构中，若条件句为否定句，not应被放在主语之后，而不能缩写成werent,shouldn或hadn而置于居首。如例15,1626含蓄型：with:“要是有，如果有”，表示与现在事实相反的假设。.Withyourhelp,wewould,haveworked,outtheproblem.(要是有你的帮助，我们早就解出这道题了。实际上你没有帮助我们，我们也没有解出这道题。).Withalittleasssistanee,Alexander.would.have,succeeded.Withbetterequipment,we,cou.l.

16、d.havedoneitbetter.a.without/butfor/ifitwerenotfor(wereitnotfor)/ifithadnfor(haditnotbeenfor)/intheabsenceof+Sb./Sthb.butthat+句子；注意：a.b.都表示要不是，若非，如果没有，如果不是”，表示与现在事实相反的假设。.Withoutyourhelp,Iwoul.dnt,have.ma(suchrapidprogress.Withouttheprogrammer(程序编制人员),thecomputerwould.beuseless.Withoutsunshine,nothi

17、ngcouldgrowonearth.Withoutwaterorair,nothing.couldive.Withoutcontradictionnothing.co.u.ld.exist.(没有矛盾，就没有世界).Withouthim,wewould,have.failed.Withoutstoughne如果没有困难，我们就不会了解伟人的坚韧性格。).Iwouldnever,make.itwithoutthehavitsoforderanddiligenee.(假如没有按部就班和勤奋的习惯，我就不会成功。).Withoutchallenges,Obamawould,never,have,b

18、eenPresidentoftheUnitedStates.Withoutsteel,there.would,benomodernindustry.没有钢，就没有现代工业。).Butfortherain,we,should.have.hadapleasantjourney.Butforyourtimelyrescue,theboy,would,have.,drowned.Butforfriction,peoplecouldneitherwalk,norevenstandup.(注:以上例句1-13without,butfor都可互换，并可替换为intheabsenceof;若是对现在或将来的虚

19、拟，可用Ifitwerenotfor替换；若是对过去的虚拟则可用Ifithadnotbeenfor来替换。).Butthathesawit,he,co.uJd,not.have.,believedit.Thelittlegirlwould,have,falLen.,into,theriverbutthatthePLAmancaughther.ButthatyoudidntlertetakethatcupofteaI.,would,have,been,posionedtodeath.She,would,have,cometoseeyouthatdaybutthatshewasill.(=Butf

20、orherillness).Butthatitsnowedheavily,theycould-have.arrived,thereearlier.(二Butfortheheavysnow,).Shewouldhaveboughttheboolbutthatshehadnomoneythen.J_dj*-.J.Ifitwerentiforob,Iwould,.comewithyou.Ifitwerenotforhiswifesmonewoeld.never.beamayor.Ifithadntbeerihfeidoctorscashou.ld,not,bespeakingtoyounow.Ifi

21、thadnotbeenforyou,Icould,not,have.worked,outtheproblem.or,orelse,otherwise.Ididntcatthebus,otherwiselwouldnt.have,m.issehefilm.Igotuptoolate,otherwiseIwouldn.thave,beeateforthemeeting.Shewasntfeelingerywell.Otherwiseshewouldn.thave,lefbemeetingsoearly.Iwasillthatday.OtherwiseIwould,have.takenpart,in

22、theparade游行).Iambusynow.OtherwiseIwould.helpyou.Hecanthavewrittenme,otherwiseIwould.have,gothisletterbynow.Hetoldmeofyourarrival,orIwould,have.knownnothingaboutit.Thesoldierfledaway,orhewould,.have.been.killed.Ididntknothathewasaliar,orelseIwouldn.t.have.be.l.ievetim.通过上下文推断，没有引导词，真正的含蓄。学者).Iwould,d

23、osoinyourposition.Givenmoretime,we,would.doitbetter.Unlessyou.had,doneitearlier,you,wouldhave,failed.suppose(that),supposing(that);provided(that);assuming(that);onconditionthat;giventhat.Suppose/supposingthatthere,.werenogravity,objects,.would,not.falltogroundwhendropped.=Iftherewerenogravity,object

24、s.would.not,falltogroundwhendropped.Supposingyoucouldn.t,wrjte/hatwouldyoudo?.Childrenwere,permitted,.into,thehallforthefilmprovided(that)theydid.not,.makeanytrouble.Theguardsallowthetouriststogointothewoodsonconditionthatthey(should)donoharmtotheanimals.(onconditionthat=onlyif,它所引导从句的谓语动词的语气可陈述，可虚拟

25、，但均表示一个真实条件。).Giventhathedoesntagrfeedoit,weshalldoitalone.(giventhat表示一个真实条件，其从句谓语动词用陈述语气。)宾语从句的虚拟语气wishwishthathaddome表示对过去已发事情的虚拟wishthatdid/were表示对现在正发事情的虚拟wishthatwereto/should/could/might/woulddof表示对将来要发事情的虚拟.IwishIwereabird.Theuglygirlwishesshe_werebetterlooking.SometimesIwishIwere.livinginad

26、ifferenttimeandadifferentplace.HowIwisheveryfamilyhad.alargehousewithabeautifulgarden!.IhaveneverbeentoNewYork,buthowIwishI.had.IwishIcould.fly.tothemooninaspaceshiponeday.Howwewishwecould.havearesttomorrow!.IwishIcould.standonabusystreetcorner,hatinhand,andbe.gpeopletothrowmealltheirwastedhours.(我希

27、望自己站在熙熙攘攘的大街上，手里拿着帽子，乞求人们把废弃的时光扔给我。).IwishIhadnever.methim.Iwishyouhadnt,sp.enbmuchmoney.wouldrather(that)本结构从句是一般过去时时，表示一个对现在或将来的愿望；是过去完成时时，表示对过去已发事件的一种妄想，表明说话者宁愿某人做或没有做某事，实际上却恰恰相反。具有相同用法的结构还有wouldsooner,wouldassoon,wouldjustassoon它们可替换wouldrather。.Iwouldratheryouwerehomenow.Idsoonerpaiutedthewallg

28、reennexttime.Iwouldratheryouhad.beentherewithme.实际上不是你，是别人).Idratheryedmorehealththanwealth.Idratheryouhadnthtatto(实际上已做).IwouldratherthatIhadstayedathomeyesterday实际上并没有).IwouldjustassoonthatJohnhadnt.spokeudelytome.Idratherhadtoldmethetruth.Idrathereveryting.hadn.enedbetwappus.试比较：、wouldrather后接动词原

29、形，表示对现在或将来某种行为的一种主观愿望或选择，为陈述语气。.Iwouldratherstayathomethangotothecinema.Thebravesoldierswouldtather_diethansurrendertotheenemy.Idratnorgotothecinematonight.、wouldrather后接不定式完成时表示对已发生事件的后悔。.Irathernothavetoldherthenews.Sheissuchagossip.Thefilmwasterrible.Inbtdhsathgipnetothecinemalastnight.-Didyoubla

30、mehimforhismistakes?-Yes,butIfatdiernothavedoneit.3.3.表示愿望、建议、请求、命令等含义的动词331这类动词的宾语从句的谓语形式为should+动词原形，should可以省略,但引导词that通常不省略。常用的这类动词有：advise忠告，建议ask要求command命令decide决定demand要求desire希望，可望determine决定insist坚持order命令prefer宁愿promise允诺propose提议recommend推荐，劝告request要求require要求suggest建议332巧记宾从用虚拟语气的动词方法一

31、、一坚二命三建四要一坚持tinsist二命令torder,command四要求三建议tsuggest,advise,recommendrequire,request,demand,desire方法二、DISCO(迪斯科)DtdemandCtcommand方法三、Idropcaps.ItinsistDtdemandCtcommand方法三、Idropcaps.ItinsistItinsistOtorderDtdemand/desirerequire/request/recommendOtorderPtproposeAtadvisePtprefer333例句StsuggestRCtcommandS

32、tsuggest.Thedriverdemandedthatallthepassengers.showtheirticketstohim.Theofficerorderedthathistroopsmove.ontothefront.Thecommandercommandedthatwe.attackatonce.Inthepastmengenerallypreferredthattheirwivesworkinthehome.Ipreferthatyounot.eatthatmuch.IproposethatMr.Libe.thechairman.Irecommendedthatyousho

33、uld.reduceyourexpenditure.Heasksthathebe.givenanopportunitytotrythismethod.IaskedthatIbeallowedtoseeher.Heinsistedthatadoctor.b.e.sent.foratonce.Ourteacherinsistedthatwe.not.playcomputergamesatschool.Whodoyousuggesbe.senttoworkthere?.Wesuggesthathe.givelessmoneytohischild.Mr.WangsuggestedthatI.takee

34、noughsleepbeforethefinalexamination.Hedeterminedthatshe.set.offatonce.Sheadvisedthatwe.keepthedoorlocked.Theyrequirethatvisitors.not.smokeintheworkshop.Mr.Wangrequiredthatallthestudents.bepolitetoothers.注：以上各例句宾语从句中谓语动词前统统省略了should。、suggest与insist之例外suggest作“建议”解时用虚拟语气，作“表明”解时用陈述语气；insist作“坚持”解时用虚拟语

35、气，作“坚持认为，坚持说”解时用陈述语气。.Thesmileonmymotherfacesuggestedthatshewasdelightedwithmyexaminationresult.(非虚拟).Hisyawnssuggestedhathewassleepy.(非虚拟).Allthesefactssuggesthathejsinnocent.(非虚拟).Janespalesuggestedhatshewasill,andhisparentssuggestedhatshehaveamedicalexamination.前实后虚).Heinsistedthathehaddoneright.

36、(非虚拟).HeinsistedthathewasnotinvoIvedinthecase.(非虚拟).Heinsistedthathehadnotbeenlatethatmorning.(非虚拟).Heinsistedthatwhathesaidwastrueandweinsistedthathego.and.havealook.(前实后虚).Theagedmaninsistedthathewasnitlandshouldn.,t.be.stthehospital.主语从句的虚拟语气基本结构：Itbe/seem+(表示愿望、建议、命令、要求、意志、惊讶、不满、遗憾等意义的)形容词/过去分词/

37、名词+that+主语+(should)+动词原形在本结构中it是形式主语，真正的主语是后面的that从句，从句中谓语动词的形式为shoulddo,should可以省略。Itis+adj.+that+(should)doamazing令人吃惊的essential重要的natural自然的surprising令人惊讶的astonishing令人惊讶的常用的此类形容词有：advisable明智的disappointing令人失望的embarrassing令人尴尬的important重要的incredible令人难以置信的necessary必需的，不可缺少的strange奇怪的vital至关重要的ur

38、gent紧急的imperative势在必行的.Itisnaturalthatheobject_toaplanlikethat.Itisnecessarythatwetellhimthetruthatonce.Itisnotnecessaryhateveryonebeascientist.Itisessentialthateverychildbe_giventhesameeducationalopportunities.Itisurgentthatadoctorshould,be_sentforimmediately.Itisadvisablethateveryone,haveamap.Itis

39、vitalthattheheadmaster,receivethisletterthisevening.Itisimportantthatyoushould.thankthosewhosupportedyouthroughthedisappointments.(重要的是，你应该感谢那些在你失意时给予你支持的人。).Itisreallystrangethatthegirlbemarriedsoearly.(真奇怪，那小姑娘竟然这么早就出嫁了！).Itisamazingthatheshould,have,ea.rntsomuchinsuchashorttime.Itisstrangethathe,

40、have,efitwithoutsayinggood-bye.Itissurprisingthathe,should,besofoolishastobelieveherlie.Itwasastonishingthatshehave,ke.ptthesecretfromhimallthroughtheirlifetime.Itseemsincrediblethathe,have,.finishedtheworksosoon.(他竟然这么快就完成了工作，这似乎令人难以置信。)在Itisamazing/surprising/astonishing/strange/incrediable/apity/

41、ashamethat.结构中，that虚拟从句表示说话人的惊讶、懊悔、失望等强烈的情感，含有“竟然，居然”的意思，表明所发生的事情非常出人意料。如上面例句9-14。再如：.Itapisythatheshould,missthelecture.(真遗憾，他竟然错过了这次演讲。).Itaisythathe,should,turn,downmyoffer.真遗憾，他竟然拒绝了我的提议。).Itisashamethatshe,should,behavelikethat.她竟然表现的那么差劲，真丢人。)本结构还可形变为Itis+of+上述形容词相对应的名词形式+that(should)do。如：.Iti

42、sofutmostimportancethatyoubehereontime.42Itis+过去分词+that(should)do常见的此类过去分词有：suggestedordereddesiredproposeddecidedrecommendedrequestedrequireddemanded1).Itissuggestedthatmoretreesshouldbeplantedtopreventsandatorms.Itisrequiredthatthestudents.wearschooluniformsatschool.Itisdecidedthatnosmoking.beallo

43、wedinthelibrary.Itisdemandedthatoneofthestudents.should.staytolookafterthethings.Itisproposedthatthismatter.be.consideredatthenextmeeting.Itisrecommendedthattheworkshouldn,.t.besta.rteidtilallthepreparationshavebeenmade.表语从句的虚拟语气基本结构：(表示提议、建议、命令、要求的)名词+be+that+主语+(should)+动词原形.常见的此类名词有：advicedecisio

44、ndemandideaorderplanrecommendationproposalrequestsuggestionpitydesirewishrequirement1).Mysuggestionisthatwe.should.tryourbesttohelptherefugeesoftheearthquakes.Thecommanderorderwasthatsoliders.set.outatonce.Ourideaisthatthematch.be.putoff.Ourdecisionisthattheschool.remainclosed.ThedoctoradVioewasthat

45、you.give.upsmoking.Hispropoalisthatthematter.be.discussedatthenextmeeting.Ourwishisthathe.should.dowhathepleases.Mydesireisthatallthemembersofthefamily.gatheronceayear.同位语从句的虚拟语气基本结构：(表示提议、建议、命令、要求的)名词+that+主语+常见的此类(should)+动词原形.名词有:advicedecisiondemandideaorderplanrecommendationproposalrequestsugge

46、stionpitydesirewishrequirement1).Thepeopleexpressedtheirdesirethatthewarcome.to,an.endassoonaspossible.Whatdoyouthinkofmysuggestiorkhatwesendafewworkerstohelptheothegroups?.Iagreedtotheideathatadoctorbe.sent.for.Mr.Wangavscethatweshould.go.overourplanoncemoreisreasonable.Iamallfortheproposalthataspe

47、cialgroup,be.set.uptolookintothematter.Itismydesirethatallthemembersofthefamilygatheronceayear.gJJBlnIBJ定语从句的虚拟语气基本结构：Itis(high,about)time+that+主语+动词过去式.Itis(high,about)time+that+主语+shoulddo.(注意：should不能省略,that可以省略。)本结构表示“目前该做却还没有做的事”，该事早就该做了，时间已经有些晚了。.Itishightimethatwewereoff.Itistimethatsomeone.t

48、aughtyoutobehaveyourself.Itsabouttimethahweid.putanendtothiscontroversy争论，正义).Itishightimethatweshould,.prepareforthefinal.Itabouttimeweshould.considerwhattodonext.Itstimsek/tework.(set为过去式).Itstimstarted./set.off/.set.out./left.Itstimfoundsomewheretoeat.注:句型Itstimetodosth./Itstimeforsb.todosth./It表

49、示stime“该做某事了，是做某事的时候了”，没有“目前该做却还没有做的事”的含义。其它类虚拟语气asif/though属于时态型虚拟语气，其动词结构与wish之后的虚拟语气相同。过去haddone现在did(be用were)将来wereto/should/could/might/woulddo.ShespeaksEnglishveryfluentlyasthoughshewereborninEngland.(实际上不是).Themantalkedtoomuchasthoughheweredrunk.(实际上说话人认为他并未喝醉).Hetalkedasifhehadtakenpartinthe

50、LongMarch.Heoperatedthemachineasifhewereaskilledworker.Irememberthewholethingasifithadhappenedyesterday.Itwouldbeanexcellentruletoliveeachdayasifweshoulddietomorrow.注：以上例句1-6asif/though引导的是方式状语从句；但如果主句的动词是系动词be,feel,look,seem,sound,appea等时，asif/though弓丨导的便是表语从句了。如下列例句7-11。.MaryfeltasthoughMr.Wangwer

51、eherfather.Whenapencilispartlyinaglassofwater,itlooksasifitwerebroken.Heappearedasifhehadknownnothingaboutit.他看上去对此一无所知。).Ifeelasifwehadknowneachotherforages.注意：asif/though之后即可接虚拟语气，又可接陈述语气，试比较：.Itlooksasif/thoughitmightrain.(好像天要下雨。虚拟语气，与将来事实相反，实际上不会。).Itlooksasifitisgoingtorain.(陈述语气，实际上确实会下雨。)eve

52、nif/though引导的让步状语从句属于时态型虚拟语气，说的不一定是事实，往往表示一种虚拟的让步，其时态结构与if引导的虚拟条件句一样。过去haddone现在did(be用were)将来1、did;2、shoulddo;3、weretodo.EvenifIwererich,Iwouldwork.IwontlendyoumoneyevenifIhadmoney.EventhoughIhadbeenwithyouthen,Icouldnothavehelpedyou.Wewouldntloseheartevenifweshouldfailonehundredtimes.Evenifhehadbe

53、enthere,Ishouldhavesaidthesamething.Eventhoughyouhadenoughmoney,youcouldnotbuythelosttime.Itisbettertoinvitehimeventhoughheshouldrufuse.注意：Evenif/though也可引导陈述语气的句子，表达一种真实的让步。试比较：.Evenifitrainstomorrow,Iwillgosightingwithyou.(情况真实，确实照办).EvenifIbecomeamillionaire,Ishallalwaysbeasocialist.(陈述语气)83ifonl

54、y(二HowIwish)引导的虚拟语气属于时态型虚拟语气，表示一种强烈的愿望、遗憾或不满，意为“要是就好了”，“但愿”。.IfonlyIhadmoremoney!Icouldbuysomenewclothes.IfonlyIhadnotcheatedintheexamination!.Ifonlywehaddoneasweweretold!Thiswouldneverhavehappened.IfonlyIweretenyearsyounger!.Ifonlyyouhadtoldmeinadvanee!.IfonlyIhadnotmarriedbeforeImetyou!.Ifonlyyouh

55、adarrivedalittleearlier!注意：ifonly与onlyif的区别：onlyif中only只起到加强、突出的作用，if的词义并为改变，意为“只有在条件下”，表示条件的唯一性。如：.OnlyifyouhelpmecanIsucceed.Iwillgohomeonlyifyougowithme.-WillyoucometoBirthdayPartytomorrow?-OnlyifyoupromisenottoinviteTom.8.4.lest,forfearthat引导的目的状语从句基本结构：lest(forfearthat)+主语+隶属should型should+动词原形虚

56、拟语气，其后动词用should+动词原形，should可换为might,would,也可以省略，意味“以免，为了不”。.Shetookataxitothestationlestsheshouldmissthetrain.(=Shetookataxitothestationsothat(或inorderthat)sheshouldnotmissthetrain.=Shetookataxitothestationincasesheshouldmissthetrain.).Heremindedhertwiceofitlestsheshouldforget.Shealwaysstudieshardle

57、stshelagbehind.Neverletchildrenplaywithfirelesttheymightsetfiretothehouses.IquietlyenteredtheroomlestIshouldwakeupmybaby.Hismotherpunishedhimlestheshouldmakethesamemistakeagain.Heburnedalltheimportantdocumentslesttheyshouldfallintotheenemyhands.Weighwellyourwordslesttheybeswords.Wemustnotpromisewhat

58、weshouldnot,lestwebecalledontoperformwhatwecannot.注：以上例句1-9中lest都可被forfearthat替换。85whetheror引导的让步状语从句意为“不管/不论是还是”，结构为：whether+主语+be+表语一+or+表语二，.Whetherheberichorpoor,Iwillmarryhim.(可省略whether,此时要到装:Beherichorpoor,.).Whetheritbeneworold,itismybike.(=Beitneworold,itismybike.).Behefriendorfoe,thelawreg

59、ardshimascriminal.(二Whetherhebefriendorfoe,).Whetherthefiguresbeaccurateornot,mtheyhavetoberechecked.Betheycommonpeopleorhigh-rankingofficials(高官)theystandequalbeforethelaw.Everymorninghegoesjoggingalongthelake,whetheritbefineorrainy.ShecantranslateallthesebooksintoChinese,betheyEnglish,FrenchorLati

60、n.Whetherthiscriticismbewiseorfoolish,importantorinsignificant,itisatleastnatured.（不管这批评是明智的还是愚蠢的，重要的还是无关紧要的，至少它是善意的。）8.6.表示祝愿、礼貌的虚拟语气861LongliveChairmanMao!（live不加-s）Godblessyou!Godblessyou!(bless不力口-es)862Maysb.dosth!&Wishsb.sth!Wishyousuccess!Wishyouagoodtrip.Wishyouagoodbirthday.Mayyousucceed!宀.