状语从句的时态特点

涉及状语从句的几种特定时态1.“主将从现”原则即若主句为一般将来时，时间和条件状语从句通常要用一般现在时表示将来，而不能直接使用将来时态。如：I’llgiveherthetelexwhenshecomes.她来时把电传交给她。I’llreturnthebookassoonasIhavereadit.这书一看完我就送还。He’llhavefouryearsatuniversityafterheleavesschool.他中学毕业后要上四年大学。2.since与完成时since引导时间状语从句时，其主句通常要用现在完成时，有时也用现在完成进行时。如：ShehashadanotherbabysinceIsawherlast.从上次我见到她以来，她又生了一个孩子。HehasgrownaninchsinceIsawhim.我上次见到他以后他已长高了一英寸。注：当主句为“It+be+一段时间”时，则通常用一般现在时代替现在完成时。如：It’smorethanthreeyearsnowsinceIsawherlast.我们已有三年多没见面了。3.特定句式的时态由nosooner...than,hardly[scarcely]…when引出的时间状语从句，其主句通常用过去完成时，从句通常用一般过去时。如：Hardlyhadhearrivedwhenshestartedcomplaining.他刚到她就抱怨起来。Nosoonerhadhegonetosleepthanthetelephonerang.他刚睡着电话铃就响了。Wehadnosoonersetoutthanathunderstormbroke.我们刚出发就下起一阵雷暴。Nosoonerhadsheagreedtomarryhimthanshestartedtohaveterribledoubts.她刚同意嫁给他她就开始产生可怕的疑虑。状语从句的时态特点一般情况下，时间和条件状语从句的谓语动词一般用“一般现在时”表示“一般将来时”，用“现在完成时”表示“将来完成时”。例如：IwillcallyouassoonasIarriveinBeijing.我一到北京就给你打电话。（这是由assoonas引导的时间状语从句，从句中的谓语动词arrive是一般现在时，表示一般将来时，决不可用willarrive）AssoonasIhavefinishedthiswork,Iwillgohome.我一完成此工作，就回家。（从句中的谓语动词用现在完成时havefinished，表示将来完成时,决不可用willhavefinished）Ifhecomesback,pleaseletmeknow.如果他回来了，请通知我。（从句中的谓语动词用comesback,表示一般将来时，决不可用willcomeback）状语从句讲解和练习状语修饰动词、形容词、副词或整个句子。通常由副词、介词短语、动词不定式、分词和从句等担当。例如：1.Naturally,ourgrandparentswerepleasedtogetourphonecall.(副词)2.Weworkedhard,fromsunrisetosunset.(介词状短语)3.Tohelpmydisabledaunt,Ispendanhourworkinginherhouseeveryday.(不定式)4.Seenfromadistance,thefarmhouselookeddeserted.(过去分词)5.IknowhowtolightacampfirebecauseIhaddoneitbefore.（原因状语从句）状语的位置比较灵活，可以位于句首、句末或句中。enough用作状语修饰形容词和副词时必须后置。状语从句主要用来修饰主句或主句的谓语。一般可分为九大类，分别表示时间、地点、原因、目的、结果、条件、让步、比较和方式。尽管种类较多，但由于状语从句与汉语结构和用法相似，所以理解和掌握它并不难。状语从句的关键是要掌握引导不同状语从句的常用连接词和特殊的连接词即考点。现分别列举如下:1．时间状语从句常用引导词：when,as,while,assoonas,before,after,since,till,until特殊引导词：theminute,themoment,thesecond,everytime,theday，theinstant,immediately,directly,nosooner…than,hardly…when,scarcely…whenIdidn’trealizehowspecialmymotherwasuntilIbecameanadult.WhileJohnwaswatchingTV,hiswifewascooking.Thechildrenranawayfromtheorchard(果园)themomenttheysawtheguard.NosoonerhadIarrivedhomethanitbegantorain.EverytimeIlistentoyouradvice,Igetintotrouble.2．地点状语从句常用引导词：where特殊引导词：wherever,anywhere,everywhereGenerally,airwillbeheavilypollutedwheretherearefactories.Whereveryougo,youshouldworkhard.3．原因状语从句常用引导词：because,since,as,for特殊引导词：seeingthat,nowthat,inthat,consideringthat,giventhat.MyfriendsdislikemebecauseI’mhandsomeandsuccessful.Nowthateverybodyhascome,let’sbeginourconference.Thehigherincometaxisharmfulinthatitmaydiscouragepeoplefromtryingtoearnmore.Consideringthatheisnomorethan12yearsold,hisheightof1.80misquiteremarkable.4．目的状语从句常用引导词：sothat,inorderthat特殊引导词：lest,incase,forfearthat，inthehopethat,forthepurposethat,totheendthatThebossaskedthesecretarytohurryupwiththeletterssothathecouldsignthem.Theteacherraisedhisvoiceonpurposethatthestudentsinthebackcouldhearmoreclearly.5．结果状语从句常用引导词：so…that,so…that,such…that,特殊引导词：suchthat,tothedegreethat,totheextentthat,tosuchadegreethat,Hegotupsoearlythathecaughtthefirstbus.It’ssuchagoodchancethatwemustnotmissit.Tosuchandegreewasheexcitedthathecouldn’tsleeplastnight.6．条件状语从句常用引导词：if,unless,特殊引导词：as/solongas,onlyif,providing/providedthat,supposingthat,incasethat,onconditionthatWe’llstartourprojectifthepresidentagrees.Youwillcertainlysucceedsolongasyoukeepontrying.Providedthatthereisnoopposition,weshallholdthemeetinghere.7．让步状语从句常用引导词：though,although,evenif,eventhough特殊引导词：as(用在让步状语从句中必须要倒装)，while(一般用在句首)，nomatter…，inspiteofthefactthat,while,whatever,whoever,wherever,whenever,however,whicheverMuchasIrespecthim,Ican’tagreetohisproposal.尽管我很尊敬他，我却不同意他的建议。Theoldmanalwaysenjoysswimmingeventhoughtheweatherisrough.Nomatterhowhardhetried,shecouldnotchangehermind.Hewon’tlistenwhateveryoumaysay.8．比较状语从句常用引导词：as(同级比较),than(不同程度的比较)特殊引导词：themore…themore…;justas…，so…;AistoBwhat/asXistoY;no…morethan;notAsomuchasBSheisasbad-temperedashermother.Thehouseisthreetimesasbigasours.Themoreyouexercise,thehealthieryouwillbe.Foodistomenwhatoilistomachine.食物之于人，犹如油之于机器。9．方式状语从句常用引导词：as,asif,how特殊引导词：thewayWheninRome,doastheRomando.Shebehavedasifsheweretheboss.Sometimesweteachourchildrenthewayourparentshavetaughtus.10.状语从句的简化♠状语从句的省略状语从句同时具备下列两个条件:①主句和从句的主语一致，或从句主语为it；②从句主要动词是be的某种形式。从句中的主语和be动词常可省略。例如：When(themuseumis)completed,themuseumwillbeopentothepublicnextyear.He’llgototheseasideforhisholidayif(itis)possible.另外，比较状语从句经常省略。例如：I’mtallerthanhe(istall).Thehigherthetemperature(is),thegreaterthepressure(is).就状语从句而言,有时为了使语言言简意赅,常常将状语从句进行简化。状语从句的简化现象在口语中较为普遍,而且在高考中的复现率也较高。因此,有必要对其进行全面、透彻的了解。状语从句的简化现象常存在于以下五种状语从句中:①由if,unless等引导的条件状语从句;②由although,though,evenif/though等引导的让步状语从句;③由when,while,as,before,after,until/till等引导的时间状语从句;④由as,asif等引导的方式状语从句;⑤由as,than等引导的比较状语从句。下面针对这五种情形作一归纳。(1)当状语从句的主语是it,且谓语动词是be时,it和be要完全简化掉。例如:If(itis)possible,hewillhelpyououtofthedifficulty.如果可能的话,他会帮你摆脱困境。Youmustattendthemeetingunless(itis)inconvenienttoyou.除非情况对你来说不方便,否则你必须出席这次会议。(2)当状语从句的主语和主句的主语一致时,从句可以将主语和be动词简化掉。常用于以下几种情形:a.连词+形容词As(hewas)young,helearnedhowtorideabi