2023年定語從句知識(shí)點(diǎn)匯總

定語從句◆英語諺語欣賞1.Hewhoknowsnothingbutpretendstoknoweverythingisindeedagood-for–nothing.不懂裝懂，一事無成.2.It’sthefirststepthatcosts.千里之行，始于足下3.Hethatmakeshimselfasheepshallbeeatenbythewolf.甘當(dāng)小綿羊，遲早要喂狼.Ⅰ.概念：(1)定語從句：在主從復(fù)合句中用作定語的從句叫定語從句。定語從句一般緊接在先行詞(antecedent)后面。(2)先行詞：被定語從句修飾的成份。先行詞可認(rèn)為一個(gè)詞，短語，或整個(gè)主句。(3)引導(dǎo)定語從句的詞叫關(guān)系詞，分為關(guān)系代詞和關(guān)系副詞。關(guān)系詞的作用：1)引導(dǎo)定語從句，連接主句和從句，相稱于一個(gè)連詞；2)必在從句中作某個(gè)句子成份（可以做主語，賓語，表語，定語，狀語）常用的關(guān)系代詞:that、which、who、whom、whose、as常用的關(guān)系副詞（在從句中只作狀語）:when、why、whereThestudentwhoansweredthequestionwasJohn.Iknowthereasonwhyhewassoangry.Theboy(whom)youaretalkingtoismybrother.I'dlikearoomwhosewindowlooksoutoverthesea.定語從句三步：第一找出先行詞；第二看先行詞在定語從句中的語法功能（做主語、賓語或狀語）；第三選擇合適的關(guān)系詞。Ⅱ.幾個(gè)關(guān)系代詞的基本用法：●that:可指人或物；在定語從句中作主語，賓語，表語。(指人時(shí)，相稱于who或whom；指物時(shí)，相稱于which)(一般不用于非限制性定語從句;不可置于介詞后作賓語)如：1.Aletterthat/whichiswritteninpencilisdifficulttoread.(主語)2.Doyouknowthegentlemanthat/whospokejustnow?3.Youcantakeanything(that)youlike.（賓語）4.Whatisthequestion(that/which)theyaretalkingabout?5.Hereistheman(who/whom/that)youwanttosee.6.She'snolongerthegirl(that)sheusedtobebefore.（表語）7.Ourhometownisnolongertheone(that)itusedtobe.=Ourhometownisnotthesameasitusedtobe.=Ourhometownisdifferentfromwhatitusedtobe。=Ourhometownisnotwhatitusedtobe.●which:指物；在定語從句中作主語，賓語，表語，定語。如：1.Thebookwhich/thatwasonthedeskwasboughtbymyfather.（主語）2.Thebook(which/that)Iboughtyesterdayisveryinteresting.（賓語）3.Thefactoryinwhichhisfatherworksisfarfromhere.4.Hewasproud,whichhisbrotherneverwas.（表語）5.Tomspentfouryearsincollege,duringwhichtimehelearnedFrench.（定語）6.Hemaybelate,inwhichcaseweoughttowaitforhim.●who,whom,whose:who:主格,在從句中作主語，在口語或非正式用法中作賓語;只可指人whom:賓格，在從句中作賓語;只可指人whose:屬格，在從句中作定語，可指人也可指物。Ilikethestudentswho/thatworkhard.（主語）Allwhoheardthestorywereamazed.(代詞如he,they,any,those,all,one等后多用who.)Chaplin,forwhomlifehadoncebeenveryhard,wasasuccessasanactor.（賓語）He'samanfromwhomweshouldlearn.=He'saman(whom/who/that)weshouldlearnfrom.Achildwhoseparentsaredeadiscalledanorphan.（指人）I'dlikearoomwhosewindowfacessouth.（指物）=I'dlikearoomofwhichthewindowfacessouth.=I'dlikearoomthewindowofwhichfacessouth.ThereisateapotshapedlikeaChineseduck,outofwhosemouthteaissupposedtocome1.

關(guān)系代詞whose，引導(dǎo)定語從句時(shí)，既可指人，又可指物，在從句中只能作定語；ofwhom只能指人；ofwhich只能指物，有時(shí)whose可以與ofwhom和ofwhich互換使用。如：ThegirlwhosehairisgoldenisfromEngland.頭發(fā)金色的那個(gè)女孩是英國(guó)人。Thehousewhosedoorsaregreenisanofficebuilding.門是綠色的那座房子是辦公樓。2.

“介詞+whose+名詞”引導(dǎo)定語從句。如：Ilovemymotherland,forwhosegoodfutureIwillworkhard.我愛我的祖國(guó)，為了她美好的未來我要努力工作。3.

在下列情況下，一般只用ofwhom和ofwhich。(1)

定語從句的主語是few,little,some,most,many,much等時(shí)，一般只用ofwhom和ofwhich。Intheroomarelotsofpeople,manyofwhomIdon’tknow.房間里有很多人，很多人我不結(jié)識(shí)。Hehasalotofstory-books,afewofwhichIhaveneverread.他有很多故事書，有幾本故事書我還從未看過。(2)

定語從句的主語是數(shù)詞、形容詞的最高級(jí)時(shí)，一般只用ofwhom和ofwhich。如：Theoldmanhasthreechildren,twoofwhomarecollegestudentsandoneofwhomisamanager.那個(gè)老人有三個(gè)小孩，其中兩個(gè)是大學(xué)生，另一個(gè)是經(jīng)理。(3)

定語從句的主語是all,none,both,neither,each等不定代詞時(shí)，一般只用ofwhom和ofwhich。如：Therearefiftystudentsinourclass,allofwhomareworkinghard.我們班有五十個(gè)學(xué)生，所有這五十個(gè)學(xué)生學(xué)習(xí)都刻苦。Heplantedtwotreeslastyear,bothofwhicharegrowingwell.去年他栽了兩棵樹，這兩棵樹都長(zhǎng)得好。(4)

在定語從句中作表語的定語時(shí)，一般只用ofwhom和ofwhich。如：Hehasthreebrothers,ofwhomLiLeiistheyoungestone.它有三兄弟，李蕾是他們中最小的一個(gè)。TherearemanycountriesinAsia,ofwhichChinaisthelargestone.亞洲有很多國(guó)家，中國(guó)是最大的一個(gè)。關(guān)系代詞作介詞賓語:關(guān)系代詞在定語從句中用作介詞賓語時(shí),介詞可放于從句之首,也可放于從句之末.但以放于句首較為正式.（介詞前置，必須注意不影響動(dòng)詞詞組的含義。關(guān)系代詞who和that用作介詞賓語時(shí),介詞必須放在句末.）關(guān)系代詞前介詞選擇三原則：一先，二動(dòng)，三意義（重中之重）1.一先，即根據(jù)定語從句中介詞與先行詞的搭配關(guān)系選擇。IneverforgetthedayonwhichIcametothisschool.(ontheday)2.二動(dòng)，即根據(jù)定語從句中謂語動(dòng)詞與介詞的搭配關(guān)系選擇。ThisistheiPadonwhichIspent3000yuan.(spendmoneyonsth.)3.三意義，即根據(jù)定語從句的意義來擬定介詞。Thisismypairofglasses,withoutwhichIcannotseeclearly.Thisisthebookforwhichyouasked.=Thisisthebook(that/which)youaskedfor.DoyouknowthepersonwithwhomIshookhands？=Doyouknowtheperson(whom/who/that)Ishookhandswith?Thebeginningofagriculturewasabigstepinhumanprogresswithwhichnothingcouldcompareuntilourinformationage.Inthedarkstreet,therewasn'tasinglepersontowhomshecouldturnforhelp.Isthisthefactorytowhichyoupaidavisitlastweek?Isthisfactorytheonetowhichyoupaidavisitlastweek?Thisisthegirlwhomtheyarelookingafter.(介詞after與look構(gòu)成固定詞組，不可前置。lookat,lookfor,lookafter,takecareof,hearof\about\from,carefor,lookforward,payattentionto,listento等)●as的用法:(as引導(dǎo)定語從句,在定語從句中作主語、賓語、表語)①如為限制性的，多用于thesame…as;thesameas；such…as…;asmany/muchas；so…as等結(jié)構(gòu)中。如：※Ihavethesamebookasyou(have).我有一本和你的同樣的書。Herattitudetohimwasquitethesameasithadalwaysbeen.(關(guān)系代詞as和指示代詞same連用,在從句中用作表語,先行詞是same.).---Whydidn'tyoumentionthatinfaceofthepolicejustnow?---Ithoughtitwassuchaminordetailaswashardlyworthmentioning.Wewillonlydiscusssuchproblemsashavesomethingtodowithourowninterests.Don'tdosuchthingsasyouarenotsureabout.Thereisnosuchplaceasyoudreamofinallthisworld.比較：Iliveinthesamehousethatheusedtolivein.I'mwearingthesameshirtasyouworeyesterday.比較：Hereissobigastoneasnoonecanlift.（定語從句）Hereissobigastonethatnoonecanliftit.（結(jié)果狀語從句）②如為非限制性的，多單獨(dú)引導(dǎo)一個(gè)定語從句，這種定語從句可置于句首，句中或句尾，譯為"正如，這一點(diǎn)"。（動(dòng)詞常為know,see,expect,pointout,etc.）Asweallknow,smokingisharmfultoone'shealth.(as作賓語)=Asisknowntoall,smokingisharmfultoone'shealth.（as作主語）=It'sknowntoallthatsmokingisharmfultoone'shealth.=Smokingisharmfultoone'shealth,asweallknow.（as作賓語）=Smoking,asweallknow,isharmfultoone'health.Hewasaforeigner,asIknewfromhisaccent.(賓語,先行詞是前面整個(gè)句子)Ⅲ.關(guān)系副詞引導(dǎo)的定語從句:●When指時(shí)間，在定語從句中作時(shí)間狀語。其先行詞是表時(shí)間的名詞（如：time,day,week,tear,month,etc.）HecamelastnightwhenIwasout.Wewillputoffthepicnicuntilnextweek,whentheweatherwouldbebetter.注意：先行詞為"時(shí)間名詞"，可用when引導(dǎo)定語從句，when在定語從句中作狀語；還可以用which或that引導(dǎo)，which或that在從句中作主語或賓語。比較:Istillrememberthedaywhen/onwhichmybrotherjoinedthearmy.（作狀語）Nextmonth,whenyouwillbeinyourhometown,isjustaroundthecorner.Istillrememberthedayswhich/thatwespenttogether.（作賓語）Nextwinterwhich/thatyou'llspendinHarbin,I'msure,willbeexciting.IshallneverforgetthedaywhenShenZhouⅤwaslaunched,whichhasagreateffectonmylife.Thereareoccasionswhenjokingisnotpermissible.●Where指地點(diǎn)，在定語從句中作地點(diǎn)狀語。其先行詞是表達(dá)地點(diǎn)的名詞，如：place,school,factory,room,etc.ThisistheplacewhereIwasborn.Iliveintheroomwhere/inwhichheusedtolive.注意：先行詞是"地點(diǎn)名詞"，定語從句可用where引導(dǎo)，還可用which或that引導(dǎo)，which/that在從句中作主語或賓語。比較:※Thisisthefactorywhere/inwhichheworkedlastyear.（作狀語）

在高中的英語學(xué)習(xí)中，我們都知道，where在定語從句中用作關(guān)系副詞，作狀語，先行詞一般指地點(diǎn)。例如：

Thisisthefarmwhereweworkedwhenwewereyoung.

這就是我們年輕時(shí)候在此干活的農(nóng)場(chǎng)。

Hemethiswifeintheparkwheretheyfellinlovewitheachother.他是在這個(gè)公園碰到他的妻子，就是在那里，他們相愛了。

當(dāng)然，在實(shí)際的英語學(xué)習(xí)中，where在定語從句中的用法遠(yuǎn)不是這么簡(jiǎn)樸，相反，要復(fù)雜得多，為了讓學(xué)生對(duì)where在定語從句中的用法有更好的了解，下面我就對(duì)學(xué)生在學(xué)習(xí)過程中的重難點(diǎn)問題談一談它的用法。

一、某些在從句中充本地點(diǎn)狀語的“介詞+關(guān)系詞”結(jié)構(gòu)可以與where互換，where=in/at/on/...which

例如：ThisisthehouseinwhichIlivedtwoyearsago.這是我兩年前住過的房子。

ThisisthehousewhereIlivedtwoyearsago.

在英語學(xué)習(xí)中，并不是單純地讓學(xué)生知道where的這種用法就可以了，很多時(shí)候?qū)W生要掌握where和其他詞的用法的區(qū)別，才干更好地把握定語從句的用法。例如：

Thisisthefactorywhere/inwhichyouworkedlastyear.

Thisisthefactorythat/which/youvisitedlastyear.

在第一句中，關(guān)系詞在定語從句中作狀語，所以用關(guān)系副詞where或者inwhich，由于定語從句中worked是個(gè)不及物動(dòng)詞；而在第二句中，關(guān)系詞在定語從句中做賓語，因此用that或which，還可以省略，visited是個(gè)及物動(dòng)詞。學(xué)生有時(shí)還會(huì)碰到更復(fù)雜的情況。例如：

Isthisfactorytheonethat/which/\youvisitedlastyear?

Isthisfactorytheonewhere/inwhichyoulivedlastyear?

Isthisthefactorywhere/inwhichyoulivedlastyear?

這幾個(gè)句子比前面的兩個(gè)句子又復(fù)雜，除了要區(qū)別關(guān)系詞在定語句子作什么成分，還要注意到前兩個(gè)句子缺成分，所以要補(bǔ)充theone。

二、where定語從句修飾抽象名詞

where引導(dǎo)的定語從句的先行詞大多數(shù)情況下是表達(dá)地點(diǎn)的名詞，但也有特殊情況。假如定語從句修飾point，situation，part，condition和case等表達(dá)抽象意義的詞，關(guān)系詞在定語從句中充當(dāng)狀語時(shí)，常用where引導(dǎo)，意思是“到了某種地步，在某種境況中”。為了幫助同學(xué)們熟悉這一語言現(xiàn)象，對(duì)的掌握這一知識(shí)點(diǎn)，對(duì)where定語從句修飾抽象名詞的用法作一歸納。

1)

where定語從句修飾抽象名詞point

Youreachapointwheremedicinecan’thelp.你已到了藥物無法治療的地步。

Wehavereachedapointwhereachangeisneeded.我們到了必須改一改的地步。

注：有時(shí)point也可以是具體的地點(diǎn)：

TheaccidenthappenedatthepointwheretheA15joinstheM1.事故發(fā)生在A15與M1交叉的十字路口。

2)

where定語從句修飾抽象名詞case

Therearecaseswheretheword“mighty”isusedasanadverb.在一些情況下，mighty一詞可用作副詞。

3)

where定語從句修飾抽象名詞activity

Thosesuccessfuldeafdancersthinkthatdancingisanactivitywheresightmattersmorethanhearing.那些失聰?shù)某晒ξ璧秆輪T們認(rèn)為，舞蹈是一種讓人看勝過讓人聽的活動(dòng)。

4)

where定語從句修飾抽象名詞situation

Hegotintoasituationwhereitishardtodecidewhatisrightandwrong.他陷入一種難以分辨是非的局面。

5)

where定語從句修飾抽象名詞position

It’sputmeinapositionwhereIcan’taffordtotakethejob.這使我陷入一種不能接受此工作的境地。

6)

where定語從句修飾抽象名詞job

Shewantsajobwherehermanagementskillscanbeputtogooduse.她想找一份能將她的管理技能派上用場(chǎng)的工作。

當(dāng)然了，我們碰到這些詞作為先行詞時(shí)并不一定都用where，我們也要具體情況具體分析，他們只有在定語從句中作狀語時(shí)才用where。

例如：Wearetryingtoreachapoint____bothsideswillsitdowntogetherandtalk.

A.which

B.that

C.where

D.when

---Doyouhaveanythingtosayforyourself?

---Yes,there’sonepoint____wemustinsiston.

A.why

B.where

C.how

D./

上面兩個(gè)句子雖然先行詞相同，都是point，但是由于他們?cè)诙ㄕZ從句中充當(dāng)?shù)某煞植煌?，所以我們?cè)谶x擇關(guān)系詞時(shí)就要區(qū)別對(duì)待。第一個(gè)句子中關(guān)系詞在句中作狀語，所以選擇where關(guān)系副詞；第二個(gè)句子中關(guān)系詞在定語從句中做賓語，所以選擇關(guān)系代詞that，which或者不填，這樣第一題選擇C，第二題選擇D。Thetreatmentwillcontinueuntilthepatientreachesthepointwherehecanwalkcorrectlyandsafely.Ithinkyouhavegottothepointwhereachangeisneeded,oryouwouldfail.Governmentreports,legalpapersandmostbusinesslettersarethemainsituationswhereEnglishisused.He'sgothimselfintoadangeroussituationwherehe'slikelytolosecontroloftheplane.Thesmallmountainvillagewherewespentourholidaylastmonthliesinwhat/theplacewhichisnowpartofHubei.Thisistheparkwhich/thattheyvisitedlastyear.（作賓語）Nothavingbeentherebefore,hesimplyhadnoideaabouttheplace,whicheveryonesaysisworthvisiting.●Why指因素，在定語從句中作因素狀語。先行詞為reason時(shí)，可用forwhich指代；當(dāng)關(guān)系詞在從句中作主語或賓語時(shí)，則用which或that引導(dǎo)。如：Thereasonwhy/forwhich/(that)hedidn'tattendthemeetingwasthathewasill.Idon'tbelievethereason(that/which)hegaveme.（作賓語）Haveyouaskedhimthereasonthatmayexplainhissuccess?（作主語）Ex.)Hewaslate.That'sbecausehegotuplate..Hegotuplate.That'swhyhewaslate.(表語從句)(thereason)why/forwhichhewaslate.(定語從句)當(dāng)先行詞為way時(shí)，定語從句常用that,inwhich,或不用引導(dǎo)。way后的定語從句的引導(dǎo)詞不用時(shí)較多。但假如關(guān)系詞在句中作主語或賓語時(shí)，則用which或that引導(dǎo)。如:Thisistheway(that)/inwhichIdosuchthings.比較:Pleasedotheexperimentintheway（that/which）Ihaveshownyou.Ⅳ.限制性定語從句與非限制性定語從句的區(qū)別：1.形式上，非限制性定語從句往往用逗號(hào)隔開。2.語法上，非限制性定語從句一般不用that.3.語義上，限制性定語從句與先行詞關(guān)系緊密，起限定作用，假如去掉了這個(gè)定語從句，整個(gè)句子就不完整或者會(huì)改變意思；而非限制性定語從句與先行詞關(guān)系不是很緊密，對(duì)先行詞起補(bǔ)充說明或描述的作用。ThisisthebookIlikebest.這就是我最喜歡的那本書。Beijing,whichhasbeenChina'scapitalformorethan800years,isrichinculturalandhistoricrelics.北京是中國(guó)八百年之久的古都，它有著豐富的文化和歷史遺產(chǎn)。4.翻譯時(shí)，限制性定語從句可譯為一句（較短的一般譯為"的"字結(jié)構(gòu)）；而非限制性定語從句可譯為兩句。（見上句翻譯）比較:Hehasasister,whoisamusician.Hehasasisterwhoisamusician.引導(dǎo)非限制性定語從句的關(guān)系代詞，指人時(shí)用who,whom,whose,指物時(shí)用which,whose;關(guān)系副詞when，where,why,etc.1.Hestudiedhardatschoolwhenhewasyoung,whichleadstohissuccessinhislaterlife.2.Tom'sfather,whoarrivedjustnow,isafamousscientist.3.Theysetupaseparatestateoftheirown,wheretheywouldbefreetokeepNegroesasslaves.4.Hewasproud,whichhisbrotherneverwas.Ⅴ.幾個(gè)易混淆的關(guān)系代詞的比較:●that&which:在定語從句中，which和that在指代事物時(shí)，一般可以互換使用，但并非在任何情況下都是這樣，這里介紹宜用that,而不宜用which的情況.①先行詞為不定代詞,all,much,something,everything,anything,nothing,none,theone等,1.Weshoulddoallthatisusefultothepeople.2.There'snothingthatcanbesaidaboutit.3.Doyoumeantheonethatwasboughtyesterday?②先行詞被only,any,few,little,no,just,very,oneof等詞修飾時(shí)。1.Theonlythingthatwecoulddowastowait.2.That'stheverywordthatiswronglyused.Thelastplace(that)wevisitedwasthechemicalworks.Youcantakeany(=whichever)seatthatisfree.IhopethelittlethatIcanwillbeofsomehelptothem.比較*Thisisoneofthebestnovelsthatwerepublishedlastyear.*Thisistheonlyoneofthebestnovelsthatwaspublishedlastyear.③先行詞是序數(shù)詞時(shí)或被序數(shù)詞修飾時(shí)。1.WhenwetalkaboutWuxi,thefirstthatcomesintomindisTaiLake.2.Thisisthethirdfilmthathasbeenshowninourschoolthisterm.④先行詞是最高級(jí)或被最高級(jí)修飾時(shí)。1.Thisisthebestthatcanbedonenow.2.Themostimportantthingthatshouldbedonerightnowishowtostophimfromgoingon.⑤先行詞既有人又有物，用which和who都不適合，這時(shí)宜用that.如：1.Thewriterandhisnovelthatyouhavejusttalkedaboutisreallywellknown.2.Theriderandhisbikethathadrunoveranoldwomanwereheldupbythepolice.⑥被修飾詞為數(shù)詞時(shí).1.YesterdayIcaughttwofishandputtheminabasinofwater.Nowyoucanseethetwothatarestillalive.⑦假如有兩個(gè)從句，其中一個(gè)關(guān)系代詞已用which,另一個(gè)關(guān)系代詞宜用that，以避免語言的單調(diào)或反復(fù)。Edisonbuiltupafactorywhichproducedthingsthathadneverbeenseenbefore.⑧疑問詞是who或which，關(guān)系代詞宜用that，以避免反復(fù)。1.Whichisthebookthatyoulikebest?2.Whoisthemanthatisstandingatthegate?⑨主句是Therebe結(jié)構(gòu)，修飾其主句的定語從句宜用that作關(guān)系代詞.如：1.Thereisstillaseatinthecornerthatisstillfree.⑩被修飾成分為表語時(shí)，或者關(guān)系代詞自身是定語從句的表語時(shí),該關(guān)系代詞宜用that.1.That'sagoodbookthatwillhelpyoualot.2.Myhomevillageisnolongertheplace(that)itusedtobe.定語從句中宜用which而不宜用that的情況:①當(dāng)關(guān)系代詞的前面有介詞時(shí).1.Azooisaparkinwhichmanykindsofanimalsarekeptforexhibition.2.IsthistheroominwhichMr.Whitelives?②在非限制性定語從句中.1.Crusoe'sdog,whichwasarenowveryold,becameillanddied.2.MoreandmorepeoplearebeginningtolearnEnglish,whichisbecomingverypopularinourcountry.(which指代主句)③在一個(gè)句子中有兩個(gè)定語從句，其中一個(gè)定語從句的關(guān)系代詞用了that,另一個(gè)宜用which.1.Letmeshowyouthenovel，thatIborrowedfromthelibrarywhichwasnewlyopentous.2.AtthestationIboughtsomemagazinesthatmighthelpmetopassthetimeonthetrainandwhichIcouldpassontootherswhenIfinishedthem.④當(dāng)關(guān)系代詞后面帶有插入語時(shí).1.Here'stheEnglishgrammarwhich,asIhavetoldyou,willhelpimproveyourEnglish.⑤先行詞自身是that,宜用which.What'sthatwhichsheislookingat?⑥先行詞是those+復(fù)數(shù)名詞.Ashopshouldkeepastockofthosegoodswhichsellbest.(B)who&that:who和that指代人時(shí)，有些情況宜用who,而不宜用that①先行詞為anyone,anybody,those,all,one,ones,they,he,people時(shí).如：1.ThepersonIwanttolearnfromistheonewhostudieshardandworkswell.2.Anyonewho(=Whoever)failedtocometothemeetingyesterdaymustgivehisreason.3.Thosewhoarenotfitfortheirworkshouldleaveofficeatonce4.Idon'tliketheones(=those)whotalkbig.5.Personswhoarequarrelsomearedespised.②在Therebe結(jié)構(gòu)中，修飾主語的定語從句宜用關(guān)系代詞who指代人.如：1.Thereisagentlemanwhowantstoseeyou.2.Thereareseveralstudentsinourclasswhoarestillnotsureabouttheuseofattributiveclauses.③當(dāng)先行詞有較長(zhǎng)的后置定語時(shí).如：1.ImetaforeignerintheparkyesterdayafternoonwhocouldspeakChineseverywell.④一個(gè)句子中帶有兩個(gè)定語從句，其中一個(gè)定語從句的關(guān)系代詞是that,另一個(gè)則宜用who,以免反復(fù).如：Thestudentthatwaspraisedatyesterday'smeetingisthemonitorwhoisverymodestandworksveryhard.which與as引導(dǎo)非限制性定語從句的異同一、相同點(diǎn)兩者引導(dǎo)非限制性定語從句時(shí)，可指代主句中的部分或整個(gè)句子的內(nèi)容，在從句中做主語，賓語或表語，位于主句之后有時(shí)可互換。Themeetingwasputoff,as/whichwasexactlywhatwewanted.Hewasadoctor,as/whichIknewfromhismanner.二、不同點(diǎn)1.as可以放在主句前后，也可插入主句之中；而which引導(dǎo)的非限制性從句只能位于主句之后。Asisknowntoall,fishcan’tlivewithoutwater.Air,asweknow,isgas.2.在非限制性從句中，which后的be動(dòng)詞不可??；as而后的be動(dòng)詞可以省略。Shetoldmeshewonthematch,whichwasalie.Thematerialiselastic,as(was)showninthefigure.3.which在非限制性定語從句做主語時(shí)可用各類動(dòng)詞做謂語；而as做主語時(shí)，謂語常用系動(dòng)詞，如be,seem,become等，一般不用其他行為動(dòng)詞。Hesawthegirl,whichdelightedhim.Hedidn’tsayanythingatthemeeting,as/whichseemedverystrange.4.as常用“正如”含義，常用的結(jié)構(gòu)有asweknow（眾所周知）；asoftenhappens（正如常發(fā)生的那樣）；asisoftenthecase（情況經(jīng)常如此）;asweallcansee（正如我們看到的）;beannounced/expected/known/imagined/mentioned/said/shown/reported等。這些結(jié)構(gòu)常放句首，偶爾也可以放句中或句末。Asisknowntoall,Chinaisadevelopingcountry.Katewaslateforschool,asoftenhappened.5.在非限制性定語從句中which指代主句中某一個(gè)單詞時(shí)，as不可以。Mybrotherenjoyedplayingbasketball,whichhereallyplayswell.Beijing,whichhewasbornin,isourcapital.6.“介詞+關(guān)系代詞（介賓代物）”中關(guān)系代詞只能用which。TheTravelAgency,withwhichourcompanyhasbeendealingforseveralyears,hasopenedfornewbranches.

Airisamixtureofgases,ofwhichoxygenforms21percent.7.從句中的謂語動(dòng)詞是否認(rèn)形式時(shí)，常用which。

HecanwritealetterinEnglish,whichIcannot.Metalwillbearbeatingwithahammer,whichastonewillnot

8.在非限制性定語從句關(guān)系代詞代表前面主句中的賓語從句時(shí)，常用which

Hesaidhehadpassedtheexam,whichwasuntrue.定語從句中關(guān)系代詞省略與保存我們知道，關(guān)系代詞在定語從句中作賓語時(shí)可以省略，但也有幾種特殊情況，關(guān)系代詞不用作賓語也可以省略，同學(xué)們學(xué)習(xí)和使用時(shí)請(qǐng)注意。在下列情況下,引導(dǎo)賓語從句的關(guān)聯(lián)詞可以省略。一、that在定語從句中作表語時(shí)。例如:Sheisall(that)ateachershouldbe.她具有一個(gè)老師應(yīng)當(dāng)具有的所