高中英语语法专题系列：状语从句

状语从句定义在复合句中担任状语成分的从句称为状语从句，修饰主句的谓语动词，形容词或副词等。状语从句分类1.时间状语从句2.地点状语从句3.原因状语从句4.条件状语从句5.让步状语从句6.目的状语从句7.结果状语从句8.方式状语从句9.比较状语从句1.时间状语从句常用连词：when,while,as,before,after,since,until(till),once,assoonas,themoment,immediately,each/everytime,thefirsttime,thelasttime,bythetime,whenever等引导。1）whenwhen引导从句时，主从句的动作有先有后，也可以同时进行,从句的动作可以是持续性的，也可以是短暂的。WhenIgottotheairport,theplanehadalreadytakenoff.（前后）WhenIlivedthere,IusedtogototheseasideonSundays.（持续）Whenthemovieended,thepeoplewentback.（短暂）【注意】当when引导的时间状语从句的主语与主句主语相同时，往往还可以用“when＋分词”的形式替代该状语从句。WhenIcameintotheroom,Ifoundhimlyingthereasleep.=Whencomingintotheroom,Ifoundhimlyingthereasleep.=Comingintotheroom,Ifoundhimlyingthereasleep.2）whilewhile侧重主句的动作发生在从句的时间之间，且从句的动词必须是持续性的。Whilewewerechatting,shewaslookingatthetimetableonthewall．WhileIslept,athiefbrokein.while+持续性动词3）asas表示一边…一边…，强调从句和主句中两个动作交替进行或同步进行。SometimesIwatchTVasIamhavingbreakfast．（一边...一边...）as表示随着，此用法不用when或while替Asspringwarmstheearth,allflowersbegintobloom.（随着）4）beforebefore表示在一段时间之前。HehadlearnedEnglishforthreeyearsbeforehewenttoLondon.Shedidn'tgooutbeforeshefinishedherhomework.(=not……until……)她把作业做完才出去的。before从句往往带有否定的含义，常译为：还没等到…就…；还没来得及…就...。作此意时，从句中常见情态动词can/could。ThemanhungupthephonebeforeIcouldanswerit.Healmostknockedmedownbeforehesawme.before常用句型（必背句型）①Itwillbe+时间段+before+一般现在时：要等多久才…….Itwillbefiveyearsbeforewemeetagain.②Itwon'tbelongbefore+一般现在时：等不了多久就会……Itwillnotbelongbeforeyouregretwhatyouhavedone.③Itwas+时间段+before+一般过去时：等了多久就……Itwasminutesbeforethepolicearrived.④Itwasn'tlongbefore+一般过去时：没等多久就……ItwasnotlongbeforeIrealizedIwaswrong.【比较】Itis/hasbeen+时间段+since+一般过去时：自从……以来到现在已经有多长时间Itisthreeyearssincethewarbrokeout.【注意】Itisthreeyearssincehesmoked.他不吸烟已有3年了。Itisthreeyearssincehehassmoked.他吸烟已有3年了。5）unitl/tilltill和until引导时间状语从句时跟主句里肯定形式表示延续性动作的谓语动词连用表示“到……为止”。Walkuntil/tillyoucometoawhitehouse.Iwillstaywithheruntil/tillhecomesback.till和until跟主句里否定形式表示非延续性动作的谓语动词连用表示“直到……才(开始)”，这时until和till可用before代替。Not有时被no,nobody,nothing,never,hardly,little等否定词所取代。Peopledonotknowthevalueoftheirhealthtill/until/beforetheyloseit.Don’tputoffwhatyoucandotodayuntiltomorrow.今日事，今日毕。=Neverputoffwhatyoucandotodayuntiltomorrow.【until常见考点】结构A：Notuntil+时间状语(从句)+主句倒装句Notuntilshegothomedidsherealizethatshehadlosthernecklace.结构B：Itis(was)notuntil+时间状语(从句)+that+主句强调句ItwasnotuntilyesterdaythatIrememberedit.ItwasnotuntilIsawMargaretnextmorningthatIfelthappy.6）sincesince自……以来。主句中通常为延续性动词的现在完成时，since从句中一般用短暂性动词的一般过去时。WherehaveyoubeensinceIlastsawyou？Itisthreeyearssincehebegantosmoke.since还可以用作副词或介词。Youhavemadegreatachievementsinyourworksincegraduation.=Youhavemadegreatachievementsinyourworksinceyougraduated.7）assoonasassoonas...可译为“一…就…”。Hewillcomeandseeyouassoonashegetshome.（主将从现）【注意】一…就…还可以用on/upondoing结构来表示。OnarrivinghomehecalledupLester.=Assoonashearrivedhome,hecalledupLester.【补充】immediately/instantly/directly和themoment,theminute,theinstant,thesecond这几个名词短语相当于assoonas，直接引导时间状语从句，表示一…就…。Theyphonedherimmediatelytheyreachedhome.Telephonemethemoment(that)yougettheresults.8）scarely/hardly…when…nosooner…than…scarely/hardly…when…；nosooner…than…都表示刚……就……，主句通常用过去完成时,从句用一般过去时。Hehadnosoonerstartedoutthanhefelthomesick.Hehadhardlystartedhisspeechwhensomeonerosetorefutehispoints.【注意】当hardly/scarcely,nosooner位于句子的开头时，主句须用倒装语序。Hardlyhadshefallenasleepwhenaknockatthedoorwokeherup.NosoonerhadIgothomethanitbegantorain.9）onceonce作连词时，一旦，但它含有的条件意味更浓。Onceyoubegin,youmustcontinue.Onceyouseehim,youwillneverforgethim.10）nexttime,thefirsttime等nexttime,thefirsttime,thelasttime,everytime,anytime,eachtime直接引导时间状语从句。Besuretocallonusnexttimeyoucometotown.IlovedthispicturethefirsttimeIsawit.【区别】I'vebeenhereforthefirsttime.（副词）11）bythetimebythetime也可以引导时间状语从句，意为到….时为止，主句一般要用完成时态。Bythetimehewasfourteen,Einsteinhadlearnedadvancedmathematicsallbyhimself.Iwillhavefinishedmyworkbythetimeyoureturn.经典例题1.IwassofamiliarwithhimthatIrecognizedhisvoice______Ipickedupthephone.A.whileB.afterC.IncaseD.theminute答案：D2.Howlongdoyouthinkitwilltake_______ourproductbecomespopularwiththeconsumers?A.whenB.untilC.beforeD.since答案：C3.______thedaywenton,theweathergotworse.A.WithB.sinceC.AsD.While答案：C4.Hewashalfwaythroughhismeal____afamiliarvoicecametohisears.A.whyB.whereC.whenD.while答案：C5.Hardly______intothevillage______itbegantorain.A.wehadgot;whenB.wegot;thanC.hadwegot;whenD.didweget;than答案：C2.地点状语从句常用连词：where,wherever,everywhere,anywhereWhereIlive,thereareplentyoftrees.我住的地方树很多。Everywheretheywent,theywerekindlyreceived.无论他们去哪里，都受到热情的款待。【注意】在地点状语从句之前，不要使用介词。误：Youshouldputthebookatwhereitwas.正：Youshouldputthebookwhereitwas.误：Weshouldgotowhereweareneededmost.正：Weshouldgowhereweareneededmost.【注意】区别where引导的定语从句和状语从句。Putthebookwhereitwas.（状语从句）=Putthebookattheplacewhereitwas.（定语从句）1.Whenhereadsabook,hishabitistomakeamark_______themeaningisuncleartohim.A.thereB.whereverC.theplaceD.inwhich答案：B2.Ifyouaretravelling______thecustomsaretotallydifferentfromyourown,youmayfeelaculturalshock.A.intheplaceB.whichC.inwhichD.where答案：D经典例题3.原因状语从句常用连词：as,because,since,now(that),consideringthat,see