三大從句語(yǔ)法

從句可分為三類(lèi):即名詞性從句、形容詞性從句（即定語(yǔ)從句）和副詞性從(即狀語(yǔ)從句）。引導(dǎo)從句的詞稱(chēng)作關(guān)聯(lián)句。一、名詞性從句引導(dǎo)這些名詞性從句的關(guān)聯(lián)詞包括：從屬連詞：that，if,whether連接代詞：who,whoeverwhom,whomever，which,whichever，what,whatever，whose連接副詞where,when,why,how。其中,從屬連詞只起連接作用，在從句中不充當(dāng)任何句法成分，而連接代詞和連接副詞既起連接作用,在從句中又充當(dāng)一定的成分。不可省略的連詞介詞后的連詞 2。引導(dǎo)主語(yǔ)從句和同位語(yǔ)從句的連詞不可省略。Thatshewaschosenmadeusveryhappy。Weheardthenewsthatourteamhadwon。whether與if均為whether不能被if:。whether引導(dǎo)主語(yǔ)從句并在句首。引導(dǎo)表語(yǔ)從句3.whether4."or例：Whetherhewillcomeisnot。Thefactisthathedidn'tgotothedinner。Idon'tknowifhewillattendthemeeting。,it置于句末。That—從句作主語(yǔ)通常用it作先行詞，而將that—從句置于句末，例如：Itisquiteclearthatthewholeprojectisdoomedtofailure。很清楚，整個(gè)計(jì)劃注定要失敗。It’sapitythatyoushouldhavetoleave.你非走不可真是件憾事.用it作形式主語(yǔ)的that—從句有以下四種不同的搭配關(guān)系:AIt+be+形容+that—從句例:Itisnecessarythat…有必…… Itisimportantthat…重要的…… Itisobviousthat…很明……B.It+be+—ed分+that-從句 例如isbelieved人們相…… Itisknowntoallthat…從所周…… Ithasbeendecidedthat…已決……C。It+be+名+that—從句 例:Itiscommonknowledgethat………是常識(shí) Itisasurprisethat…令人驚奇的…… Itisafactthat…事實(shí)……D.It+不及物動(dòng)+that—分句 例：Itappearsthat…似…… Ithappensthat…巧…… Itoccurredtomethat…我突然想……為保持句子平衡，that引導(dǎo)的賓語(yǔ)從句也常用it句末。這常常出現(xiàn)在主句有形容詞或分詞作賓語(yǔ)補(bǔ)足語(yǔ)的情況下。Hemadeitquiteclearthathepreferredtolivehere。從屬連詞whether和if都作是…"解,但if不可引導(dǎo)主語(yǔ)從句和表語(yǔ)從句whether可與or(not）連,而if不可. Idon'tknowwhethersheisathome.Whethershecomesornotmakesnodifference。4。thatwhat引導(dǎo)名詞性從句的區(qū)別：that,what,.that,what.Healwaysmeanswhathesays. Shesuggested(that)hedoitatonce.5.同位語(yǔ)從句大多由從屬連詞that引導(dǎo)，常跟在下列名詞后面，如fact,idea，opinion，news，hope，belief等，that不可省。同位語(yǔ)從句一般用來(lái)解釋說(shuō)明這些名詞的具體含義和內(nèi)容。Wearefamiliarwiththeideathatallmatterconsistsofatoms.Thenewsthatweareinvitedtotheconferenceisveryencouraging.二、形容詞性從句引導(dǎo)定語(yǔ)從句的關(guān)聯(lián)詞包括：(1)關(guān)系代詞which,whose,who,as; 關(guān)系副:when，where，why.關(guān)系代詞和關(guān)系副詞在定語(yǔ)從句中都充當(dāng)一定的句法成分,關(guān)系代詞在句中充當(dāng)動(dòng)詞的賓語(yǔ)時(shí)，一般可省去。關(guān)系代詞的選用比較復(fù)雜，它受下列條件的制約: (1）先行詞是指還是指物(2）關(guān)系代詞在從句中的句法功能(3）定語(yǔ)從句是限定性的還是非限定性的。關(guān)系代詞的選用情況見(jiàn)下表：先行詞在從句中的句法功能用于限定性或非限定性定語(yǔ)從句只用于限定性定語(yǔ)從指人或指物 指人指物主語(yǔ) who which that賓語(yǔ) whomwhich that定語(yǔ) whosewhose(ofwhich)Iknowthatheisamanwho（that)meanswhatbesays.Thegentlemanwhom（that)shemetaddressedherwithcourtesy(禮貌).Thewatchwhich（that)waslosthasbeenfound。Hereisthemeterialwhich（that)youneed.You'retheonlyonewhoseadvicehemightlistento.time,day等，則用place,housearea等,則用wherereason。例：I'llneverforgetthemountainvillagewhere(inIspentmychildhood.Idon’tknowthereasonwhy(forwhich）hedidthat.1。當(dāng)先行詞是allsomethingnothing;或先行詞前有few，much,some，any,no等修飾時(shí)；或先行詞前有形容詞最高級(jí)修時(shí)，一般只用that而不用whichexplainedeverything（that)Icanto。Thisisthemostbeautifulcompus（that）I'veeverbeento。定語(yǔ)從句分為限定性定語(yǔ)從句和非限定性定語(yǔ)從句，限定性定語(yǔ)從句與主句關(guān)系緊密,,,,句一般不用that引導(dǎo)。引導(dǎo)非限定性定語(yǔ)從句的關(guān)系詞不可省略。Hisspeech,whichboredeveryone,wentonandon.Thegeneral’sdaughter,whosenameisAnn，gavemeasweetsmile..,一般用which或aswhich在從句中可,aswhichaswhich,as,,又可置于句首。Waterconsistsofhydrogenandwhich(as）isknownto。Ashadbeenexpected，hefinishedfirstindecathlon（十項(xiàng)全能)atthatOlympicGames。4,詞+which+whom,+that,則thatwhichthat.Thisistheringonwhichshespent1，000dollars.Oneofmycolleagueswhom(that)youarefamiliarwithwillcometoday.區(qū)分關(guān)系代詞與關(guān)系副詞方法一：用關(guān)系代詞，還是關(guān)系副詞完全取決于從句中的謂語(yǔ)動(dòng)詞。及物動(dòng)詞后面無(wú)賓語(yǔ)，就必須要求用關(guān)系代詞；而不及物動(dòng)詞則要求用關(guān)系副詞。例如：ThisisthemountainvillagewhereIstayedlastyear.I’llneverforgetthedayswhenIworkedtogetherwithyou方法二：準(zhǔn)確判斷先行詞在定語(yǔ)從句中的成分(主、謂、賓、定、狀），也能正確選擇出關(guān)系代詞/關(guān)系副詞。例1.Isthismuseum_Dyouvisitedafewdaysage?A。whereB.thatC.onwhichD。theone例2.IsthisthemuseumAtheexhibitionwasheld A.wherethatC.onwhichtheone三、副詞性從句在復(fù)合句中,起狀語(yǔ)作用的從句稱(chēng)作狀語(yǔ)從句。狀語(yǔ)從句分為:時(shí)間狀語(yǔ)從句、地點(diǎn)狀語(yǔ)從句、條件狀誤從句、原因狀語(yǔ)從句、讓步狀語(yǔ)從句、比較狀語(yǔ)從句、目的狀語(yǔ)從句、結(jié)果狀語(yǔ)從句、方式狀語(yǔ)從句。狀語(yǔ)從句可放在句首或句末.如狀語(yǔ)從句位于主語(yǔ)前,一般用逗號(hào)將其與主句隔開(kāi)。（一)時(shí)間狀語(yǔ)從句Whenyoucrossamainroad，youmustbeverycareful.Untilwelearnthefacts，wecan’tdoanythingaboutit。1。when，as，while引導(dǎo)時(shí)間狀語(yǔ)從句時(shí)都可以表示主句的動(dòng)作與從句的動(dòng)作同時(shí)發(fā)as引導(dǎo)的狀語(yǔ)從句中的動(dòng)作只能是延續(xù)的動(dòng)作或狀態(tài).,一般用while,而不用whenas發(fā)展、變化的情況時(shí)，一般用as，作“…”解。Whenshe，Ishalltellhertowaitforyou. Asshegotolder,shegotWhilePeterwasreadinghiswifewascooking。2。有些副詞和一些表示時(shí)間的名詞詞組也可用作從屬連詞，引導(dǎo)時(shí)間狀語(yǔ)從句。如instantly，immediately，directly，theday,everytime,theminute，thesecond,themoment等。Immediatelyhearrived,hestarteddescribinguswhathadhappened.Thedayhereturnedhome,hisgrandpawasalradydead.（二)條件狀語(yǔ)從句引導(dǎo)條件狀語(yǔ)從句的從屬連詞有：if，unless,as(so)longas,onlyif（只要)。Ifyoudon'tcomeontime，we'llstartoutwithoutyou.As(so）longasyoukeepontrying，you'llcertainlysucceed。注:除了以上提到的從屬連詞外，還有其它的一些詞或詞組也可引導(dǎo)條件狀語(yǔ)從句。如：providingthat，provided,，supposingthat，，supposethat,，onconditionthat,，incase等。Iwillgoprovidingthatmyexpensesarepaid。要是我的費(fèi)用有人代付我就去Supposingheisnotathome，whatthen？假如他不在家，那怎么辦?Youcanusethebicycleonconditionthatyoureturnittomorrow。只要你明天歸還,自行車(chē)你可以拿去用.Incaseshecomesback，letmeknowimmediately。假使她回來(lái)了,立刻告訴我Taketheraincoatincaseitrains.帶著雨衣,以防下雨。（三)原因狀語(yǔ)從句:becasue,as,inthat,consideringthat等。Consideringhe’sonlybeenlearningEnglishayearhespeaksitverywell?？紤]到他只學(xué)了一年英語(yǔ)，他講得算是很流利了。Wedidn’tknowwhattodoaswewerejustvisitingthere。我們不知道該怎么辦，因?yàn)楫?dāng)時(shí)我們僅僅在那里作訪問(wèn)。Sinceitissohot，let'sgoswimming。既然天氣這么熱,我們?nèi)ビ斡景伞Ｗhat和的用: inthat引導(dǎo)的從句對(duì)主句進(jìn)行解釋和說(shuō)明意思是：在…方面,在于…；因?yàn)?。now（that)表示既然。Theoryisvaluableinthatitcanprovideadirectionforpractice.理論所以有價(jià)值,就在于它能給實(shí)踐指出方向。Now(that）theweatherhasimproved,let'sgooutforapicnic.既然天氣已轉(zhuǎn)好，我們就出去野餐吧.(四）讓步狀語(yǔ)從句引導(dǎo)讓步狀語(yǔ)從句的從屬連詞有： though,although,evenif(eventhough)，as, nomatter…despitethefactthat，inspiteofthefactthat,while。Tiredashewas，hesatuplate。他雖然疲倦,可仍然很晚才睡。Nomatterhowtheyslanderus,wewillnevergivein.不管他們?cè)鯓诱u謗我們，我們決不讓步。WhileIlikethecolorofthehat,Idonotlikeitsshape.雖然我喜歡這頂帽子的顏色,但我不喜歡它的形狀。ever后,相當(dāng)于nomatter+詞包括:whatever,，whenever,whoever，however。Whateverhesays,don'tbelevehim.不管他說(shuō)什么都不要想相信他。Whoeveryouare,youmustobeythetrafficregulations。(五）目的狀語(yǔ)從句引導(dǎo)目的狀語(yǔ)從句的從屬連詞有：sothat,inorder，lest，incase,forfear。Theyclimbedtothetopofthebuildinginorderthattheycouldgetaviewofthecity.AskhertohurryupwiththeseletterssothatIcansignthem.Takeanumbrellaincaseitrains。Wedarenotplayjokesonhimlestheshouldbecomeangry。我們不敢開(kāi)他玩笑生怕他動(dòng)氣。注:sothat和inorderthat的區(qū)別：sothat更常用，inorderthat更正式.sothat引導(dǎo)的從句一般置于句末，而inorderthat引導(dǎo)的從句既可置于句首,又可置于句末。Inorderthatthegrassandflowerscouldbloomagain,itwasnecessarythattherocksshould