英语三大从句

1、复合句【语法重点】复合句是由一个主句加一个或几个从句所组成的句子。从句只用作句子的一个成分，不可以独立。依据从句在句子中的作用，可分为名词性从句、定语从句和状语从句三类。（一）名词性从句名词性从句包含主语从句、表语从句、宾语从句、同位语从句。其关系词有连结词whether；疑问代词who、what、which和疑问副词when、where、how、why等。名词性从句句法构造：从主Thathewillcomeiscertain.（that不行省）属语Whethersheiscomingornotdoesntmattertoomuch.连从句（不可以用if）词宾thatIthink（that）h

2、ewillbeallrightinafewdays.语Iwentinandaskedif（=whether）theyhadacheapsuit.whether从句Iwonderwhether（不可以用if）itistrueornot.表语Thefactis（that）Ihaveneverbeenthere.从Thequestioniswhether（不可以用if）itisworthdoing.句同位Thefactthatshehadnotsaidanythingsurprisedallofus.语从Theyaskedmethequestionwhethertheworkwasworthdoin

3、g.句连主Whowillhelphimisnotknown.接语Whathesaidisveryimportant.代从句Whichsidewillwinisnotclear.词that（1）作及物动词的宾语。比如：whoIreallydontknowwhatheisdoing.whom宾Doyouknowwho/whomtheyarewaitingfor?whoseHeaskedwhosedictionaryitwas.语which从Hecanttellwhichmethodtheywillusefortheexperiment.句（2）作介词的宾语。比如：Payattentiontowha

4、ttheteachersaid.Iwonderedtowhomhehadgiventheletter.表Thatiswhatheisworriedabout.语从Thequestioniswhowillcomehere.句Thequestioniswhichteamwillwinthematch.that、if、连接副词wherewhenwhyhow主Whereshehasgoneisnotknownyet.语Whentheywillstartisnotknownyet.从句Whyhediditwasntquiteclear.Howhebecameagreatscientistisknownt

5、ousall.宾Idontknowwherewearegoingtohavethemeeting.语Pleasetellmewhenweshalldiscussourworkplan.从句Doyouknowwhyhesaidthat?WillyoutellmehowIcangettotherailwaystation?表Thatiswherehewasborn.语Thisiswhyheislate.从句Thisishowhedidit.Thequestioniswhenhewillbeback.同位Ihavenoideawhenhewillcomeback.语从Youhavenoideahow

6、worriedIwas.句Theproblemiswherewecangetsomuchmoney.名词性从句的其余用法：1）if不可以指引表语从句。连结代词who、what、whose、which不可以指引同位语从句。2）有时as、asif/though、because也能够指引表语从句，能跟表语从句的谓语动词一般为系动词be、seem、look等。比如：Thingsarenotalwaysastheyseemtobe.事情其实不老是像表面上看来的那样。Itlooksasifitweregoingtorain.Itisbecauseyoueattoomuch.3）介词宾语不可以够用which

7、来指引，而要用what来指引。比如：Wecanlearnwhatwedidnotknow.HewilltalktousaboutwhathesawintheU.S.4）连词that指引的名词性从句除能用在except、but、in后以外极少作介词的宾语，。其余一些介词的宾语从句假如由连词that指引，则需用it先行一步作形式宾语。比如：Heisagoodstudentexceptthatheiscareless.Youmaydependonitthattheywillsupportyou.5）若主句谓语动词是及物动词make、find、think、see、hear等，则把宾语从句置于宾语补足语

8、以后，用it作形式宾语。比如：Wefinditnecessarythatwepractisespoken-Englisheveryday.6）某些作表语的形容词或过去分词后常接宾语从句，如sure、happy、glad、certain、pleased、afraid、surprised、satisfied等，连词that可省略，有的语法书称之为状语从句。比如：Iamsurethathewillsucceed.IamafraidyoudontunderstandwhatIsaid.Motherwasverypleasedherdaughterhadpassedtheexams.7）连结代词whoe

9、ver、whatever、whichever也可指引宾语从句。比如：Iwillshowyouwhateveryouwanttosee.Youmaychoosewhoeveryoulike.Iwilltakewhicheverfitsthesockets.（插座）8）同位语从句一般跟在某些表示抽象观点的名词后边，用以说明名词所表示的详细内容。常跟同位语从句的名词主要有：idea、news、fact、promise、answer、belief、condition、doubt、fear、hope、order、problem、proof、question、reply、report、suggestion

10、、thought、truth等。由连词that指引同位语从句既无语法功能，也无词汇意义，不过指引词；由连词whether指引同位语从句无语法功能，但有词汇意义“能否”；由连词when、where、how指引同位语从句在句中分别作作时间、地址和方式状语。注意关系词只好用whether不可以用if表示“能否”的状况以下：A)在表语从句和同位语从句中。比如：Thequestioniswhetherthefilmisworthseeing.Thenewswhetherourteamhaswonthematchisunknown.B)在主语从句中，只有it作形式主语时whether和if均可。不然，也只

11、好用whether。比如：Whetherweshallattendthemeetinghasntbeendecidedyet.Ithasntbeendecidedwhether/ifweshallattendthemeeting.C)在介词以后（介词常常能够省略）。比如：Italldepends(on)whethertheywillsupportus.D)后边直接跟动词不定式时。比如：Hedoesntknowwhethertostayornot.E)与ornot连用时。比如：Wedidntknowwhetherornotshewasready.关系词if、whether均可使用的状况以下：A)

12、指引宾语从句，但当宾语从句能否认句时，一般用if指引。比如：Iwonderif/whetherthenewsistrueornot.Idontcareifitdoesntrain.B)在“be+形容词”以后。比如：Hewasnotsurewhether/ifitisrightorwrong.用if指引宾语从句假如会惹起歧义，应防止使用if而用whether。试比较：Pleaseletmeknowifyouwanttogo.Pleaseletmeknowwhetheryouwanttogo.（if从句既可理解为宾语从句，也可理解为条件状语从句）doubt作“思疑”解接宾语从句时，主句为一定句用w

13、hether或if，主句为否认句或疑问句用that。10）it作形式主语that所指引的主语从句常由代词it作形式主语。且wh-系列指引词指引的从句均可。比如：Itmakeseveryonehappythatthegirlisstillalive.Itdoesntmattertoomuchwhetherhescomingornot.Itisstillopentoquestionwhoistoheadthegroup.谁领导这个小组还没定下来。常以it作形式主语的句型有：It+be+形容词(obvious、true、natural、surprising、good、wonderful、funny、

14、possible、likely、certain、probable)+that从句It+be+名词词组(nowonder、anhonour、agoodthing、apity、nosurprise)+that从句It+be+过去分词(said、reported、thought、expected、decided、announced、arranged)+that从句It+seem、happen等不及物动词及短语+that从句It+doesntmatter(makesnodifference,etc)+连结代词或连结副词指引的主语从句当that指引的主语从句出此刻疑问句中时，也要以it作形式主语，而把主

15、语从句后置。比如：Isittruethatthescientistwillgiveusalecturenextweek?（二）定语从句在复合句中修饰名词或代词的从句叫定语从句。被修饰的名词或代词叫先行词。指引定语从句的关系代词有who、whom、whose、which、that等和关系副词where、when、why等。关系代词和关系副词在定语从句中担当句子成分。而指引指引非限制性定语从句的关系代词有who、whom、whose、which、ofwhich等，这些关系代词都不可以省略，往常不用关系代词that。比如：Ihavetwosisters,whoarebothstudents.关系词w

16、howhichthatwhosewherewhen指代人物、地址等动物、物、地址全部者地址时间等比如：Thisisthemanwhohelpedme.Theyhaveadogwhosebarkingdrivesmemad.Iknowthereasonwhyhecamelate.Thisistheplacewherewelivedfor5years.IwillneverforgerthedaywhenImetMr.Liu.Thedoctorwhomyouarelookingforisintheroom.注意先行词表示地址时，有时用where，有时用that指引定语从句。这时要依据从句的谓语动词是

17、及物的仍是不及物的，是及物的就用that(which),不然就用where。比如;Thisisthehousewherehelivedlastyear.Thisisthehousethat(which)hevisitedlastyear.关系代词which、who或that在限制性定语从句中作宾语时可省略。比如：Amsterdamistheplacewelikemost.Theyarelookingforaperson(who)theycanrelyon.在定语从句中，若先行词指人，其关系代词可用who、whom，也可用that。比如：Thegirlwho/thatisspeakingatth

18、emeetingisourmonitor.在以下状况下多用或须用who。关系代词在从句中作主语时。比如：Thedoctorwhotreatedmewasveryexperienced.给我治病的医生是很有经验的。先行词为all、anyone、one、ones、those、people等时。比如：Allwhoheardthenewswereexcited.全部听到这信息的人都感觉喜悦。Thosewhowanttogopleasesigntheirnameshere.想去的人请在这里署名。在非限制性定语从句中。比如：Tomsfather,whoisoversixty,stillworkshard.

19、在被分开的定语从句中。比如：AnewteacherwillcometomorrowwhowillteachyouGerman.在以therebe开头的句子中。比如：Thereisastrangewhowantstoseeyou.一个句子中带有两个定语从句，此中一个关系代词是that，另一个须用who。比如：Thestudentwhowaspraisedatthemeetingisthemonitorthatisverymodestandstudiedveryhard.在会上遇到夸奖的学生是班长，他谦逊勤学。whose指引定语从句应注意以下几点：whose指引定语从句，其先行词不单能够指人，还能

20、够指物。比如：ItwasameetingwhoseimportanceIdidntrealizeatthetime.whose在定语从句中可与它修饰的名词一同作介词宾语，与介词放在先行词与从句之间。比如：ThebossinwhosedepartmentMr.Kingworkedhadheardabouttheaccident.Tom,onwhosebikeIwenttoschoolisafriendofmine.whose的先行词指物时，可用ofwhich取代whose，但词序不一样。比如：ThenovelwhosetitleisRedandBlackisveryinteresting.(=t

21、hetitleofwhich)介词+关系代词中介词的选择介词的选摘要看三方面：一要看和先行词能否搭配；二要看和定语从句中谓语动词能否搭配；三要依据定语从句的意义来选择。比如：ThisisthecarbywhichIwenttoJinan.(bycar)Tomorrowwewillhaveameetingatwhichwewilldiscusssomeproblems.ThestudenttowhomIspokehasgonehome.(speakto)3.which和that指引定语从句的差别(atthemeeting)which在从句中作主语或谓语动词及介词的宾语。that在定语从句中能够指

22、人或物，在从句中作主语或谓语动词的宾语。但不可以放在介词后边作介词宾语。比如：Thisisthebookwhichyouwant.Thebuildingwhichstandsneartheriverisourschool.Theroominwhichthereisamachineisworkshop.TheletterthatIreceivedwasfrommyfather.1）只好用which不可以用that的状况指引非限制性定语从句。关系词在从句中作介词宾语且位于介词以后。比如：ThisisthehouseinwhichIoncelived.（2）用that的状况先行词既有人又有物时先行词

23、为不定代词修饰时（all、few、little、much、something、nothing、anything等）先行词前有形容词最高等或序数词所修饰时先行词被all、any、every、few、little、no、some等修饰或被theonly、thevery、thesame、thelast、just等修饰时关系代词在从句中作表语时therebe构造比如：Allthatwehavetodoistopractiseeveryday.ThefirstlessonthatIlearnedwillneverbeforgotten.Ihavereadallthebooks(that)yougavem

24、e.HeistheonlypersonthatIwanttotalkto.Theytalkedofthingsandpersonsthattheyrememberedintheschool.Thevillageisnolongertheonethatusedtobe.注意whom、which作介词宾语时，介词一般可放在which以前，也可放在本来的地点上，在有介词的动词固定词组中，介词只好放在本来的地点上。比如：Thisisthepersonwhomyouarelookingfor.当主句是以who或which开头的特别疑问句时，定语从句须用比如：Whoistheboythatwasherej

25、ustnow?that，免得与先行词重复。as,4.as指引的定语从句1)as用作关系代词和关系副词指引限制性定语从句，并在从句中作定语、表语或状语，组成thesamesuchas等构造。比如：Ilikethesamebookasyoudo.(as作宾语)Ishalldoitinthesamewayasyoudid.(as作状语)as指引非限制性定语从句。as在定语从句中作主语、表语或宾语，这个定语从句是说明整个句子，地点可前、可中、可后，意为“正如、仿佛”。比如：Suchstampsasyouhavecollectedareveryvaluable.Asweallknow,hestudies

26、veryhard.(as作宾语)Theyremarried,aswehadexpected.常用的这类近似插入语的句式有asissaidabove,asisknowntoall,asitis等。注意关系代词在从句中作主语时，从句的谓语动词的人称和数一定和先行词保持一致。关系代词which和as在定语从句中的差别是：which不可以放在句首，而as则能够；在句中时，as有“正如”、“就像”之意，而which则没有。同位语从句与定语从句的差别：定语从句是形容词性从句，指引词是关系词，关系词取代先行词的意思在定语从句中作成分；同位语从句是名词性从句指引词是连结词，that、whether、if在句中

27、不作任何成分，连结代词和连结副词自己意义在同位语从句中作成分。比如：A.Thenewsthattheyhadwonthegamearrivedsoon.（同位语从句）（thenews和thattheyhadwonthegame无逻辑关系）B.Thenewsthatyoutoldmeyesterdayistrue.（定语从句）（thenews在从句中相当于told的逻辑宾语）（三）状语从句状语从句在句中作状语，修饰主句中的动词、形容词或副词等。状语从句放在主句以前时，常用逗号分开；放在主句以后，一般不用逗号。状语从句分类及其常用连词：类型常用连词时间状语从句when、while、as、befor

28、e、after、since、until（till）、once、assoonas等地址状语从句where、wherever等原由状语从句because、since、as、nowthat等目的状语从句so、sothat、inorderthat、incase、lest、forfearthat等结果状语从句sothat、sothat、suchthat等条件状语从句if、unless、as/solongas、onconditionthat、incase、once、providethat等退步状语从句though、although、evenif/though、as、when、while、nomatter等

29、比较状语从句asas、notsoas、than、themorethemore等方式状语从句(just)as、asif/though等指引状语从句的常有连词用法when,while和as1）when指引的时间从句中的动词既能够是持续性动词，也能够是非持续性动词。2）while指引的时间从句中的动词往常是持续性动词。3）as指引的时间从句中的动词是持续性动词时，则重视表示从句的动作和主句的动作同时发生，意为：一边一边。比如：IwasfatwhenIwasachild.Whenthefilmended,peoplerushedoutofthehall.HetookabathwhileIwasprep

30、aringdinner.Hesangsongsashewastakingabath.注意1）when能够作并列连词，用以连结并列句，意为：这时忽然。常组成以下句式：was/weredoingwhen正在忽然。比如：Iwasworkinginthegardenwhenitbegantorain.beabouttodowhen正要忽然。比如：Wewereabouttogooutwhentherainpoureddown.beonthepointofdoingwhen正要忽然。比如：Iwasonthepointofgoingoutwhenthetelephonerang.2）when还可指引原由状语

31、从句，意为：既然，考虑到，相当于since，consideringthat。比如：HowcantheylearnanythingwhentheyspendalltheirsparetimewatchingTV?3）while也可作并列连词，意为“但是”。比如：MumwassewingwhiledadwaswatchingTV.4）while还可指引退步状语从句，意为“只管”。比如：WhileIadmithisgoodpoints,Icanseehisshortcomings.till与until1）till与until意思同样，不过till一般不放在句首。、2）主句的谓语动词假如是持续性动词，

32、主句要用一定式，意为：直到为止。3）主句的谓语动词假如是非持续性动词，主句要用否认式，意为：直到才。（4）在“Itisnotuntilthat”（直到才）句型中，要用（5）notuntil置于句首时，句子需要部分倒装。until不用till。比如：Iwillstayhereuntil/tilltherainstops.ItwasnotuntilIcamebackthathewenttobed.Hedidntgotobeduntil/tillIcameback.NotuntilIcamebackdidhegotobed.before与since1）before指引的从句中一般不用否认式谓语，常用

33、句型有：Itwas/willbe+时间段+before。Itwasnot/wontbe+时间段+before。比如：ItwaslongbeforeIcame.Itwasnotlongbeforehetoldmeaboutthisaffair.（2）since后的动词不一样，起算的时间也不一样。since+非持续性动词的过去式，从该动作发生时算起since+持续性动词的过去式，从该动作结束时算起比如：Itistwoyearssincehejoinedthearmy.Itistwoyearssincehewasasoldier.because、nowthat/since、as与for区别内涵语气可

34、否回答why可否被重申项目地点because主句前或后直接因果关系强能能as主句前或后两方都知道的原since/now弱不可以不可以主句前因that既然for并列连词，句中间接的、推测最弱不可以不可以的原由比如：Asitisraining,weshallnotgotothepark.Nowthateverybodyishere,letsbeginourmeeting.Hemustbeill,forheisabsenttoday.Itisbecausehewasillthathedidntgowithus.although、though与as1）三者都能够指引退步状语从句，although指引退

35、步状语从句时用正常语序，though可用正常语序也可用倒装语序。as一定用倒装语序，从句中的表语、状语或动词原形置于句首；若表语是名词，前置要省略冠词。比如：Heisunhappy,though/althoughhehasalotofmoney.Difficultas/thoughthetaskwas,theymanagedtofinishitintime.Childas/thoughheis,heknowsalot.2）though和although在指引退步状语从句时不行与but连用，但能够和yet连用。比如：Although/Thoughitwasraininghard,yettheyw

36、entonplayingfootball.3）though还可作副词，意为“但是，但是”。置于句末。比如：Hesaidhewouldcome;hedidnt,though.4）eventhough/if指引的退步从句中视详细状况可用陈说语气或虚构语气。比如：Eventhough/ifitisraining,wellgothere.（陈说语气）EvenifIwerebusy,Iwouldgo.（虚构语气）whetheror（不论仍是）以及疑问词+ever与nomatter+疑问词（不论/不论），也可指引退步状语从句。比如：Whetheryoubelieveornot,itistrue.Whate

37、ver（=nomatterwhat）yousay,hewontbelieveyou.Whoeveryouare（=nomatterwhoyouare）,youmustobeytherules.unless与ifnot好多状况下，二者可换用。比如：Youwillbelateunlessyouhurry/ifyoudonthurry.在以下构造中，unless与ifnot不行互相代替。（1）当ifnot指引非真切条件句时一般不行用unless。比如：IfHenryhadntbeentendedcarefully,hecouldnthavelivedsolong.（2）unless表示除外的独一条件

38、，所以常不用and连结两个unless从句，而ifnot不受此限制。比如：Ifyoudonteatfreshvegetableandyoudonthaveenoughexercise,youwontkeepit.（3）unless从句中可用否认词，ifnot从句中不行再用一个否认词Iwillgounlessnooneelsedoes.（4）在ifnot从句中，常用any、yet、either、atall等非一定词，而在unless从句中常用some、already、still、too等一定词。比如：Iwillbeangryifyouhaventspokentoheryet.Iwillbeang

39、ryunlessyouhavealreadyspokentoher.as/asif/asthoughas/asif/asthough都可指引方式状语从句，此中asif或asthough指引的从句一般用虚构语气，但假如从句中所表达的状况很可能实现，也可用陈说语气。比如：Doasyouaretoldto,oryouwillbefired.Theoldladytreatstheboyasifhewereherownson.inorderthatsothat二者都可指引目的状语从句，inorderthat指引的目的状语从句可置于句首，但sothat在指引目的状语从句时不行置于句首。比如：Hegotupearlysothat/inorderthathecouldcatchthefirstbus.Inorderthathecouldcatchthefirstbus,hegotupearly.除此以外，forfearthat、incase与lest也可指引目的状语从句，从句谓语动词要用（should）+动词原形。sothatsuchthat二者都可指引结果状语从句，注意其构造形式的差别：so+形容词/副词+that从句so+形容词+a/an+可数名词单数+thatso+many/much/few/little