让步状语从句

让步状语从句专讲,让步状语从句通常用though,although,nomatter,evenif,if,eventhough,however,whatever等引起。让步状语从句可以前置，也可以后置；前置时强调主句内容，后置时强调从句内容。有时也可以采取中位（插入句中）。,两个词同义，一般情况下可以互换使用，如：Hedidntlightthefirethough/althoughitwascold.though可以和even连用，但although不可以，Although(Eventhough)thetrafficheldusup,wegottotheairportontime.,1although和though引导的让步状语从句：,当让步状语从句是指一种假设的情况，不指事实时，通常用though，而不用although，如：Hewillneverdosuchathingthoughhe(should)beforcedto.though可以在非正式文体中用作连接性状语，而although则不行。（though可以放在句中或句末，通常用逗号隔开），如：Hesaidhewouldcome;hedidnt,though.though引导的从句可用倒装语序（即把从句中的表语或状语等放在though之前），而although不能这样用，如：Youngthoughsheis,yetsheisfitforthejob.(=Youngassheis,),有时可用副词yet,still,nevertheless(但不能用连词but)加强语气，如：Thoughheisoverseventy,yet/still/neverthelesshecanridethebike.though和although后面的主语和谓语动词be可以省略，如果这个主语和主句中的主语指同一个人或物时，如：Though(hewas)severelywounded,yetherefusedtoleavethebattlefield.Though(theywere)verytired,theycontinuedtomarchon.,2evenif,eventhough和if引导的让步状语从句：evenif与eventhough同义，常用于强调让步概念Illdoit,evenifittakesmealltheafternoon.Evenifyoufail,youcantryagain.注：if有时也可以用于让步含义，但要注意条件if与让步if的区别，试比较：Ifheispoor,howcanhebuythehouse?(条件)Ifheispoor,heisatleasthonest.(让步)(=evenif),3由as,that,though引导的特殊让步状语从句结构：在正式文体或文学作品中，为了强调让步的含义，可用as引导让步从句。但as一般不置于句首，而将从句中的表语或状语置于句首。（though,that与as一样，也可以用于这种结构），如下面几种情况：,表语的倒装：OldasIam,Icanstillfight.Tallas/thoughhewas,hecouldntreachthetopshelf.Difficultthoughthetaskwas,theymanagedtoaccomplishitintime.,谓语动词的倒装：Tryashewould,hecouldnotrememberawordofit.(=Nomatterhowhewouldtry)Tryashemight,hedidntpasstheexam.Tryasyoumay,youwillneversucceed.,状语的倒装：（这时不可在状语之前加very,much等修饰语）MuchasIadmirehimasawriter,Idonotlikehimasaman.HardasIstudied,Icouldnotcatchupwiththem.,注意事项：,如果是单数名词或形容词最高级作表语，不再用冠词，如：Childas/thathewas,heknewwhatwastherightthingtodo.Youngestasheisinourclass,hespeaksEnglishthebest.as从句可以置于主句前、主句后或句中，当as从句置于句首时，主句前可加yet，如：Mary,braveassheis,isafraidofsnakes.Richasheis,(yet)Idontenvyhim.,当作表语的形容词提前时，如果从句的主语是人称代词，那么它只能放在动词之前；如果从句的主语是名词，则可用倒装语序，也可用陈述语序，Cleverthough/asyoumaybe,youcantdothat.as从句与主句在时态上可以不一致，如：Childasheis,hewasbrave.注意区别as引导的原因从句与让步从句，Lawyerasheis,heexplainsthereasonclearly.(原因从句)Lawyerasheis,hecantexplainthereasonveryclearly.(让步从句),4eventhough和thougheventhough(=evenif)引导的从句指把握不大或假设的事情，意为“即使”、“纵然”；though引导的从句指事实，意为“尽管”、“虽然”，,例如：Hewillnotrevealthesecret,eventhoughheknowsit.(可能知道，也可能不知道。)Hewillnotrevealthesecretthoughheknowsit.(虽然知道，却不说出来。),注意比较下列各句：WhileIadmithisgoodpoints,Icanseehisshortcomings.(让步)WhileIunderstandwhatyousay,Icantagreewithyou.(让步)WhileIwasreading,thelightwentout.(时间)Heisidle,whilehisbrotherisdiligent.(转折、对比),5while引导的让步状语从句：while(=although),它引导的让步状语从句只能前置，位于句首，如：WhileIadmitthattheproblemsaredifficult,Idontagreethattheycannotbesolved.,6whetheror引导的让步状语从句：这种从句也称“选择条件-让步状语从句”，可位于主句之前或之后，如：Whetherhedrivesor(whetherhe)flies,hewillbehereontime.Whetheryoulikeitornot,youllhavetodoit.Weholdthatallcountries,(whethertheyare)bigorsmall,(whethertheyare)richorpoor,shouldbeequal.Whetheritrainsorsnows,Iwillgotonight.Shehadtogo,whetherornotshewantedit.,7由连接代词whoever,whomever,whatever,whichever引导的让步状语从句：Whoever(=nomatterwho)isunwillingtogo,Iwillgo.(whoever既相当于连接词短语nomatter连接主句与从句，又相当于疑问代词who)Whomever(=nomatterwhom)youaredealingwith,thismethodisnogood.Whatever(=nomatterwhat)happens,keepcalm.Whateverothersmaysay,youarecertainlyright.Whichever(=nomatterwhich)youchoose,wehavenoobjection.,8由连接形容词whatever或whichever引导的让步状语从句，如：Whatever(=nomatterwhat)difficultiesmayarise,wemustandcanovercomethemonebyone.(whatever既相当于nomatter连接主句与从句，又相当于疑问形容词what修饰名词difficulties。)Whichever(=nomatterwhich)roomisassignedtohim,hewillhavenoobjection.Whichevermethodyouuse,theresultismuchthesame.,9由连接副词however,wherever或whenever引导的让步状语从句。例如：However(=nomatterhow)difficultthetaskmaybe,wewillfulfilitontime.(however既相当于nomatter连接主句与从句，又相当于疑问副词how修饰difficult。)Wherever(=nomatterwhere)theywent,theywerewarmlywelcomed.WheneverImunhappy,hecheersmeup.ThedogfollowsmewhereverIgo.,10注意以上几种结构的省略形式：Howeverdifficultthetask(maybe),itwillbefulfilledontime.Howevergreatthedifficulties(maybe),wewillneverretreat.Whateverthedifficulties(maybe),theymustandcanbeovercome.,11由whenever,wherever引导的从句，同时也分别是时间状语从句和地点状语从句，这里作为让步状语从句来看待，是强调它们带有nomatterwhen,nomatterwhere的含义。在口语中用nomatter+wh-结构比较常见。例如：Nomatterwhenandhowtheinvaderscome,theywillbewipedoutclean.Itistrue,nomatterwhatyoumaysay.(可置于主句之后),原因状语从句的引导词：1.Becausebecause表示直接原因，语气最强，because所引导的原因状语从句通常位于主句之后，because所引导的句子还常用于回答why引导的特殊疑问句。e.g:IdoitbecauseIlikeit.,2.since/nowthat。通常译为“既然”，表示已知的显然的理由，语气比because弱，较为正式；nowthat，更突出事实本身。Since和nowthat所引导的原因状语从句一般位于主句之前。,e.g:既然你比较空闲，那就帮我补习数学吧。Sinceyouarefree,comeandhelpmewithmymathematics.既然你是个男子汉，就不要做这样的事了。Nowthatyouareaman,youmustnotdosuchathing.,3.As引导附带说明的“双方已知的原因”，语气比since弱，较为正式，位置较为灵活（常放于主句之前）。天还在下雨，你还是乘出租车好了。Asitisraining,youdbettertakeataxi.,4.forFor所引导的原因状语从句并非用于说明主句行为发生的直接原因，而是为了提供一些辅助性的补充说明，只能放于主句之后并且必须用逗号将其与主句隔开。e.g:他不可能见到我，因为当时我并不在那里。Hecouldnothaveseenme,forIwasnotthere.,注意：在强调句型中，强调原因状语从句时，只可用Itis/wasbecausethat而不可用since或as引导原因状语从句。由于她妈妈病了，她没和我们一起去。Itwasbecausehermotherwasillthatshedidntgowithus.,还有一些介词短语也可以表示原因。这类介词短语有：thanksto,asaresultof,becauseof,dueto,owingto等。e.g:多亏了你的帮忙，我才通过了测验。由于战争，许多人丧失了生命。Asaresultofthewar,manypeoplesliveswerelost.,Thankstoyourhelp,Ipassedthetest.,由于需求的增加，一些商品提价了。Somearticleshaveriseninpriceduetotheincreasingdemand.那班列车因天气恶劣而误点。Thetrainwaslateowingtothebadweather.,seeingthat,consideringthat,inthat等也可以引导原因状语从句。既然他没有经验，他就不合适这项工作。Seeing(that)heisinexperienced,heisnotfitforthework.考虑到这个时间交通很拥挤，我们只好再呆一会儿。Considering(that)thetrafficisheavythistimeofday,wewillhavetowaitalittlelonger.,我喜欢这座城市，但我更喜欢乡村，因为那里有更清新的空气。Ilikethecity,butIpreferthecountryinthatthereisfresherair.,注意:1.before引导的从句常用句型；Itislongbefore（过了好久才）Itisnotlongbefore(过了不久就)2.till/until(till一般不放在句首)持续性动词（肯定式）+until(直到为止)瞬间性动词（否定式）+until(直到才)强调句型；ItisnotuntilthatIwaiteduntil/tillhehadfinishedhiswork.3.since译为自从来since+瞬间性动词过去式，从该动作发生时,4.原因状语从句的连because/as/sincebecause引导原因状语从句，说明直接原因。有时也用于推测性理由表示必然的因果关系。回答why只能用because,在because前可加only，just等表示强调意义的词或否定词not.在构成强调句型时，只能用because从句不能用since或as从句。,如：2000年来没有任何人怀疑过他的观点，仅仅因为他是亚里士多德-伟大的思想家。Noonequestionedhisideaforalmost2000yearsonlybecausehewasAristotle,thegreatthinker.,注意：for可连接