Grammar考点揭密在复合句中修饰主句中的动词、形容词或副词，起状语作用的从句叫状语从句。状语从句可置主语之前，也可置主语之后。前置时，从句后用逗号与主句分开；后置时，与主句之间无标点符号。状语从句可分为时间、原因、目的、结果、条件、比较、地点、让步、方式等九类。1.when,while,as区别（不用记复习）when:从句的动作可以在主句动作之前，之后或同时发生，可以和延续性动词和非延续性动词连用eg.Whenhehadfinishedhishomework,hetookashortrest.（从句发生在主句之前）WhenIgototheairport,theguestshadleft.(从句发生在主句之后)Whenweweredancing,astrangercamein.(延续性动词)Whenhereachedhome,hehadalittlerest.(非延续性动词)while:强调主句表示的动作持续于while所指的整个时间内，只能与延续性动词连用eg：Strikewhiletheironishot.eg:Whileshewastypingtheletter,thetelephonerang.as:引导的从句表示“当……时；一边……一边……”，主句和从句的动作同时发生，强调伴随。有时可译为“随着”。eg:Theytalkedastheywalked.__As____hegrewolder,hebegantogod__As____hegrewolder,hebegantogodeaf.eaf.2表示“一…就…”的几个词（也不记哦！）1)directly,immediately,instantly,assoonas…eg:Directlythemastercamein.everyonewasquiet.eg:ItellhimthenewsassoonasIseehim.2）themoment/minute/instant/secondeg:ThemomentIheardthevoice,Iknewmymotherwascoming.3）nosooner…than,hardly…whenscarcely…when注意:nosooner/hardly/scarcely①位于句首时，用部分倒装②主句用过去完成时，从句用一般过去时eg:Hehadnosoonerarrivedhomethanhewasaskedtostartanotherjourney.他刚到家，就被邀请开始另一旅程.eg:Nosoonerhadhearrivedhomethanhewasaskedtostartonanotherjourney.eg:Hehadhardlyfallenasleepwhenhefeltasofttouchonhisshoulder.他刚要入睡，就感到肩膀上被轻轻一触。Hardlyhadhefallenasleepwhenhefeltasofttouchonhisshoulder.3.before:趁…(还没有)；…才…；还没来得及…就主句用将来时，从句通常用现在时从句用过去时，主句多用过去完成时eg:Pleasewriteitdownbeforeyouforgetit.趁你现在还没忘，把它记下来after用法正好相反eg:Itwillbefourdaysbeforetheycomeback.他们要过四天才能回来eg:MyfatherhadleftforCanadajustbeforetheletterarrived.eg:Beforeshecouldmove,sheheardaloudnoise,whichgrewtoaterribleroar.她还没有来得及动弹，就听见有很响的声音，接着就成了可怕的隆隆轰鸣声。eg:Afterwehadfinishedthework,wewenthome.Itwaslongbefore...过了很久才......Itwasnotlongbefore...没过多久就......Itwillbelongbefore...要过很久才......Itwillnotbelongbefore...要不了多久就...eg:ItwaslongbeforehemarriedWeiFang.eg:ItwasnotlongbeforehereturnedtoBeijing.没过多久他就回北京了。eg:Itwillbelongbeforehegoesabroad.要过很久他才出国。eg:Itwon’tbelongbeforewemeetagain.在It+be+时间段+before句型中若主句是一般将来时态，从句是一般现在时表将来若主句是一般过去时，从句也是一般过去时1.(2004天津)Itwasevening________wereachedthelittletownofWinchester.AthatB.untilC.sinceD.before2.(2004全国)Severalweekshadgoneby________realizedthepaintingwasmissing.A.asB.beforeC.sinceD.when3.(2005广东)TheAmericaCivilWarlastedfouryears______theNorthwonintheend.A.afterB.beforeC.whenD.then4.(2005山东)Itwassometime_______werealizedthetruth.A.whenB.untilC.sinceD.before5.(2006四川)--Whydidn‘tyoutellhimaboutthemeeting？--Herushedoutoftheclassroom_______Icouldsayaword.A.beforeB.untilC.whenD.after6.(2006福建)--Howlongdoyouthinkitwillbe__chinasendsamannedspaceshiptothemoon？--Perhapstwoorthreeyears.AwhenB.untilC.thatD.before7.It________longbeforewe________theresultoftheexperiment.A.willnotbe...willknowB.is...willknowC.willnotbe...knowD.is...know8.Scientistssayitmaybefive...
