1五、连词连词是虚词,不能在句中单独担任成分,只起连接作用。按其用法,连词可分为两大类:并列连词和从属连词。1并列连词连接具有并列关系的词、短语或句子。⒈并列关系:and,notonly…butalso…,both…and…,neither…nor…如:IusedtoliveinParisandLondon.BothJaneandJimareinterestedinfishing.Theweatherhereisneithertoocoldnortoohot.Sheisnotonlykindbutalsohonest.⒉转折关系:but,yet,while(然而),when(然而,偏偏)如:Thecarisveryoldbutitrunsveryfast.Theproblemwasalittlehard,yetIwasabletoworkitout.ThewinterinBeijingisverycoldwhilethatofKunmingiswarm.Whydidyouborrowthebookwhenyouhadone?⒊选择关系:or,not…but…,either…or…如:Wouldyouliketoliveorwouldyouliketostay?Heisnotateacherbutawriter.YoucancomeeitheronSaturdayoronSunday.⒋因果关系:for如:Itmusthaverainedlastnight,forthegroundiswetnow.Theleavesofthetreesarefalling.foralreadyautumn.25.区别①and和or⑴并列结构中,or通常用于否定句,and用于肯定句。⑵但有时and也可用于否定句。请注意其不同特点:如:Thereisnoairorwaterinthemoon.Thereisnoairandnowateronthemoon.在否定中并列结构用or连接,但含有两个否定词的句子实际被看作是肯定结构,因此要用and。判断改错:(错)Wewilldiewithoutairandwater.(错)Wecaitlivewithoutairorwater.(对)Wewilldiewithoutairorwater.(对)Wecantlivewithoutairandwater.②表示选择的并列结构⑴or意思为“否则。Imustworkhard,orIwillfailintheexam.⑵either,or意思为”或者……或者……注意谓语动词采用就近原则。EitheryouorIamright.③表示转折或对比⑴but表示转折,while表示对比。Somepeoplelovecats,whileothershatethem.⑵not…but…意思为“不是……而是……not和but后面的用词要遵循一致原则。Theywerenotthebonesofananimal,but(thebones)ofahumanbeing.③表原因关系⑴for是并列连词,不能置于含两个并列分句的句子的句首,只能将其放在两个分句中间。判断改错:(错)Forheisill,heisabsenttoday.(对)Heisabsenttoday,forheisill.④so,therefore如:Hehurthisleg,sohecoudn’tlplayinthegame.3注意:a.两个并列连词不能连用,但therefore,then,yet可以和并列连词连用。YoucanwatchTV,and/oryoucangotobed.b.although,yet但although不能与but连用。⑤注意:notonly,butalso关联两个分句时,一个分句因有否定词not而必须倒装。如:Notonlydoeshelikereadingstories,butalsohecanevenwritesome.neither…nor…意思为“既不……也不……“谓语动词采用就近原则,与nor后的词保持一致。⑥比较so和such其规律由so与such的不同词性决定。such是形容词,修饰名词或名词词组,so是副词,只能修饰形容词或副词。so还可与表示数量的形容词many,few,much,little连用,形成固定搭配。⑴somany已成固定搭配,alotof虽相当于many,但alotof为名词性的,只能用such搭配。⑵so,that与such,that之间的转换即为so与such之间的转换。2从属连词指在复合句中引导从句的连结词。4⒈常见的从属连词有:引导时间状语从句的:after,before,when,as,while,since,until,till,assoonas引导原因状语从句的:because,since,as引导让步状语从句的:although,though,nomatter(无论),evenif(though)引导条件状语从句的:if,unless,once,as(so)longas引导结果状语从句的:so,sothat,so…that…,such…that…引导目的状语从句的:so,sothat…,inorderthat…引导比较状语从句的:as…as,notso(as),as,than引导方式状语从句的:as,asif…,asthough引导地点状语从句的:where,wherever引导名词性从句(主语,宾语、表语或同位语从句)的连词主要有:that,whether,if三个。其中that和whether间或还可以引起同位从句和状语从句。⒉某些用法比较特殊的从属连词用法区别①当while,when,as引导时间状语从句时的区别:⑴while引导的状语从句中动词必须是延续性。谓语动词多为进行时,或状态动词的一般时。while的这些用法可用when代替,等于“atthetimethat,“duringthetimethat”如:Pleasekeepquietwhile(when)othersarestudying⑵when除可指一段时间外,还可用来指一点时间,等于“atthetime;when引出的时间状语从句中的谓语动词可以是终止性的,也可以是延续性的。因此主句和从句的谓语可以是一般时,进行时,或完成时。如:WhenIwentintothelab,theteacherwasdoinganexperiment.(不能用while)HeoftenmakesmistakeswhenheisspeakingEnglish(then可换成while)⑶as常可与when,while通用,但强调“一边、一边”。如:As(when/while)Iwaswalkingdownthestreet,Inoticedapolicecarinfrontofnumber37.⑷when引导的状语从句中的主语与主句主语一致,主、谓是“主语+系动词”结构时,这时主语和系动词可以省略。如:When(hewas)young.heworkedforarichman.5She'llbeheretogiveyouhelpwhen(ifitis)necessary.⑸when有时代替if,引导条件句,意为“如果”“假如”。如:I'llcomewhen(if)I'mfree.②before作连词一般表示时间,意为“在.…之前”,但有些句子中这样译就显得别扭。试看以下句子的翻译:Healmostknockedmedownbeforehesaw.他且乎把我撞倒才看见我;BeforeIcouldgetinawordhehadmeasure.没来得及插话,他已经给我量好了尺寸。③till,until作为介词式从属连词,只用于时间,引导时间状语短语或状语从句,用于否定句时,结构为not…until(till)主句谓语动词延续与非延续皆可,意为“直到……才……”。用于肯定句时,只与延续性动词连用,表示“到……为止”。如:Theyplayedvolleyballuntil(till)itgotdark.Theydidn'ttalk(延续)until(till)theinterpreter(译员)came.Hedidn'tgotobed(非延续)until(till)thehisfathercameback但是,until可以放在句首,till则不行。如:Untilthelastminuteofthematchwekeptonplaying.Notuntilhefinishedhisworkdidhegohome.(倒装)④because,since,as引导原因状语时注意使用上的区别:⑴如果原因构成句子的最主要部分,一般用because因此because引导的从句往往放在句末。用why提问的句子,一定用because回答。如:Hehadtostayathomeyesterdaybecausehewasill.⑵如原因已为人们所知,或不如句子的其他部分重要,就用as,或since。since比as更正式些。as和since引导的从句一般放在句子的开头。如:Asyouaretired,youhadbetterrest/Sinceeveryoneishere,nowlet'sbegin.⑤although和though引导让步状语从句往往用法一样,但注意以下区别:⑴although用于各种文体,而though则多用于非正式的口语或书面语中。注意由although,though引导的从句后,主句不能用but,但可用副词yet,still。如:Although/Thoughitrainedallthemorming,theystillwentonwork或yettheywentonworking.⑵though常与even连用,eventhough表示强调,意为“即使”,但不能说evenalthough。如:Eventhoughhedidn'tunderstandaword,Ideptsmiling.6⑶though可用作副词,意为“然而”,常用逗号与句子分开。lthough则不能这样使用,它只作连词。如:Itwasaquietparty,Ihadagoodtimethough.⑥once作副词译“曾经”,作为连词译“一旦”,引导条件状语从句。相当于f的加强形式。如:Idon'tbelievehewasonceathief.(once这是副词)OnceAristotle(亚里士多德)hadmadeuphismindthatheavyobjectsalwaysfellfasterthanlightobjects,hetaughasatruthtohisstudents.(once连词)⑦umless引导条件状语从句等于if…not…如:He'llacceptthejobunlessthesalaryistoolow.⑧在用asif引导的方式状语从句及表语从句中,根据情况要使用虚拟语气。例如:Hetalksasifheknewallabout.但有时也可用直陈语气。Itlooksasifitisgoingtorain.⑨whether,if引导从句的用法区别:⑴引导主语从句、表语从句或同位语从句时,用whether,不用if。如:whethertheywillgototheGreatWallisnotknown.Thequestioniswhetherwecanfinishthetaskontime.Thequestionwhetherwewilltakepartinthephysicscontesthasnotbeendecided.⑵whether可接不定式,而if则不可。如:Ihaven'tdecidedwhethertoleaveornot.⑶whether可作介词的宾语或置于句首表示强调,而if则不可。如:Everythingdependsonwhetherwehaveenoughmoney.W