高中英語語法之名詞性從句

1、高中英語語法之名詞性從句 在句子中起名詞作用的句子叫名詞性從句 (Noun Clauses）。 名詞性從句的功能相當(dāng)于名詞詞組, 它在復(fù)合句中能擔(dān)任主語、賓語、表語、同位語、介詞賓語等，因此根據(jù)它在句中不同的語法功能，名詞性從句又可分別稱為主語從句、賓語從句、表語從句和同位語從句。一、引導(dǎo)名詞性從句的連接詞引導(dǎo)名詞性從句的連接詞可分為三類：連詞：that（無任何詞意）whether,if（均表示“是否”表明從句內(nèi)容的不確定性）as if ,as though（均表示“好像”，“似乎”）以上在從句中均不充當(dāng)任何成分連接代詞：what, whatever, who, whoever, whom,w

2、hose, whichever,whomever連接副詞：when, where, how, why,how many,how much,how often不可省略的連詞：1. 介詞后的連詞2. 引導(dǎo)主語從句和同位語從句的連詞不可省略。That she was chosen made us very happy. We heard the news that our team had won.比較：whether與if 均為"是否"的意思。 但在下列情況下，只可用whether：1. whether引導(dǎo)主語從句并在句首2. 引導(dǎo)表語從句 3. whether從句作介詞賓語4

3、. 從句后有"or not" Whether he will come is not clear.大部分連接詞引導(dǎo)的主語從句都可以置于句末，用 it充當(dāng)形式主語。It is not important who will go. It is still unknown which team will win the match.二. 主語從句1、作句子主語的從句叫主語從句。主語從句通常由從屬連詞that，whether，if和連接代詞what，who，which，whatever，whoever以及連接副詞how，when，where，why等詞引導(dǎo)。that在句中無詞義，只

4、起連接作用；連接代詞和連接副詞在句中既保留自己的疑問含義、又起連接作用，在從句中充當(dāng)從句的成分。例如：What he wants to tell us is not clear. 他要跟我們說什么，還不清楚。Who will win the match is still unknown. 誰能贏得這場比賽還不得而知。It is known to us how he became a writer. 我們都知道他是如何成為一名作家的。Where the English evening will be held has not yet been announced. 英語晚會(huì)將在哪里舉行，還沒有宣

5、布。有時(shí)為避免句子頭重腳輕，常用形式主語it代替主語從句作形式主語放于句首，而把主語從句置于句末。主語從句后的謂語動(dòng)詞一般用單數(shù)形式。常用句型如下：（1） It + be + 名詞 + that從句（2）It + be + 形容詞 + that從句（3）It + be + 動(dòng)詞的過去分詞 + that從句（4）It + 不及物動(dòng)詞 + that 從句另注意在主語從句中用來表示驚奇、不相信、惋惜、理應(yīng)如此等語氣時(shí)，謂語動(dòng)詞要用虛擬語氣“(should) +do”，常用的句型有：It is necessary (important, natural, strange, etc.) that It

6、is suggested (requested, proposed, desired, etc.) that2、第一部分：常規(guī)主語從句，即句子在復(fù)合句中充當(dāng)一個(gè)主語主語從句的時(shí)態(tài)：不受主句的時(shí)態(tài)影響和限制。（1）That he finished writing the composition in such a short time surprised us all.（2）Whether we will go for an outing tomorrow remains unknown.（3）Who will be our monitor hasn't been decided yet

7、.（4） Whom we must study for is a question of great importance.（5）What caused the accident remains unknown.（6）Whatever you did is right.（7）Who the watch belongs to was lost is unknown.（8）What we need is time.（9）What we need are good doctors.小結(jié):（1)引導(dǎo)主語從句連詞有that,whether,who,what,whatever等（2)連詞位于句首不能省略（

8、3)主語從句大多數(shù)情況下視為三單,但也有例外,如例9第二部分：為了防止句子頭重腳輕，通常把形式主語it放在主語位置，真正主語擱置于句末（1）It is certain that he will win the match.（2）It is true that he has made a very important discovery in chemistry.（3）It is very likely that they will hold a meeting.（4）It is strange that he should do that.（5）It is important that we

9、all should attend the meeting.（6）It is strange that the man should have stuck to his silly ideas.（7）It is a pity that we won't be able to go to the south to spend our summer vacation.（8）It is still a mystery what caused the accident. （9）It is said that he has gone to shanghai.(=He is said to hav

10、e gone to shanghai) （10）It is known to all that the gun powder was first invented by the Chinese. （11）It is suggested that the work should be done with great care.（12）It seems that he has seen the film.(=He seems to have seen the film)（13）It happened that the two cheats were there. (=The two cheats

11、happened to be there)小結(jié):（1)以that 引出的主語從句,常以形式主語it引導(dǎo). It is +形容詞/名詞/某些動(dòng)詞ed + that 從句.（2) 在有些that從句中要用虛擬語氣 (should+do/should+have done)例句4,5,6,11.3、主語從句的用法主語從句是在復(fù)合句中充當(dāng)主語的從句，通常放在主句謂語動(dòng)詞之前或由形式主語it代替，而本身放在句子末尾。 1. It 作形式主語和it引導(dǎo)強(qiáng)調(diào)句的比較 It 作形式主語代替主語從句，主要是為了平衡句子結(jié)構(gòu)，主語從句的連接詞沒有變化。而it引導(dǎo)的強(qiáng)調(diào)句則是對句子某一部分進(jìn)行強(qiáng)調(diào)，無論強(qiáng)調(diào)的是什么成

12、分，都可用連詞that。被強(qiáng)調(diào)部分指人是也可用who/whom。例如： It is a pity that you didnt go to see the film. 2. 用it 作形式主語的結(jié)構(gòu) (1) It is 名詞從句 It is a fact that 事實(shí)是 It is an honor that 非常榮幸 It is common knowledge that 是常識(shí) (2) it is 形容詞從句 It is natural that 很自然 It is strange that 奇怪的是 (3) it 不及物動(dòng)詞從句 It seems that 似乎 It happened

13、 that 碰巧 (4) it is過去分詞從句 It is reported that 據(jù)報(bào)道 It has been proved that 已證實(shí) 3. 主語從句不可位于句首的五種情況 (1) if 引導(dǎo)的主語從句不可居于復(fù)合句句首。 (2) It is said , (reported) 結(jié)構(gòu)中的主語從句不可提前。例如： It is said that President Jingo will visit our school next week. (3) It happens, It occurs 結(jié)構(gòu)中的主語從句不可提前。例如： It occurred to him that he

14、 failed in the examination. (4) It doesnt matter how/whether 結(jié)構(gòu)中的主語從句不可提前。例如： It doesnt matter whether he is wrong or not. (5) 含主語從句的復(fù)合句是疑問句時(shí)，主語從句不可提前。例如： Is it likely that it will rain in the evening? 4. What 與that 在引導(dǎo)主語從句時(shí)的區(qū)別 What 引導(dǎo)主語從句時(shí)在從句中充當(dāng)句子成分，如主語賓語表語，而that 則不然。例如： What you said yesterday is

15、right. 三、賓語從句名詞句用作賓語的從句叫賓語從句。引導(dǎo)賓語從句的關(guān)聯(lián)詞與引導(dǎo)主語從句表語從句的關(guān)聯(lián)詞大致一樣，在句中可以作謂語動(dòng)詞或介詞及非謂語動(dòng)詞的賓語。1. 由連接詞that引導(dǎo)的賓語從句由連接詞that引導(dǎo)賓語從句時(shí)，that在句中不擔(dān)任任何成分，在口語或非正式的文體中常被省去，但如從句是并列句時(shí),第二個(gè)分句前的that不可省。例如：He has told me that he will go to Shanghai tomorrow. 他已經(jīng)告訴我他明天要去上海。We must never think (that) we are good in everything while

16、 others are good in nothing. 我們決不能認(rèn)為自己什么都好，別人什么都不好。注意：在demand、order、suggest、decide、insist, desire, request, command等表示要求、命令、建議、決定等意義的動(dòng)詞后，賓語從句常用“（should）+ 動(dòng)詞原形”。例如：I insist that she (should) do her work alone. 我堅(jiān)持要她自己工作。The commander ordered that troops (should) set off at once. 司令員命令部隊(duì)馬上出發(fā)。2. 用who，w

17、hom, which, whose, what, when, where, why, how, whoever, whatever, whichever等關(guān)聯(lián)詞引導(dǎo)的賓語從句相當(dāng)于特殊疑問句，應(yīng)注意句子語序要用陳述語序。例如：I want to know what he has told you. 我想知道他告訴了你什么。 She always thinks of how she can work well. 她總是在想怎樣能把工作做好。She will give whoever needs help a warm support. 凡需要幫助的人，她都會(huì)給予熱情的支持。3. 用whether

18、或if引導(dǎo)的賓語從句，其主語和謂語的順序也不能顛倒，仍保持陳述句語序。此外，whether與if 在作“是否”的意思講時(shí)在下列情況下一般只能用whether，不用if：a. 引導(dǎo)主語從句并在句首時(shí)；b. 引導(dǎo)表語從句時(shí)；c . 引導(dǎo)從句作介詞賓語時(shí)；d. 從句后有“or not”時(shí)；e. 后接動(dòng)詞不定式時(shí)。例如：Whether there is life on the moon is an interesting question. 月球上有沒有生命是個(gè)有趣的問題。 The question is whether she should have a low opinion of the tes

19、t?現(xiàn)在的問題是她是否應(yīng)該有一個(gè)低意見的測試？ Everything depends on whether we have enough money. 一切要看我們是否有足夠的錢。 I wonder whether he will come or not. 我想知道他來還是不來。 Can you tell me whether to go or to stay? 你能否告訴我是去還是留？4. 注意賓語從句中的時(shí)態(tài)呼應(yīng)，當(dāng)主句動(dòng)詞是現(xiàn)在時(shí)，從句根據(jù)自身的句子情況，而使用不同時(shí)態(tài)。例如：he studies English every day. （從句用一般現(xiàn)在時(shí)）he studied Engli

20、sh last term. （從句用一般過去時(shí)）I know (that) he will study English next year. （從句用一般將來時(shí)）he has studied English since 1998. （從句用現(xiàn)在完成時(shí)）當(dāng)主句動(dòng)詞是過去時(shí)態(tài)（could, would除外），從句則要用相應(yīng)的過去時(shí)態(tài)，如一般過去時(shí)，過去進(jìn)行時(shí)，過去將來時(shí)等；當(dāng)從句表示的是客觀真理，科學(xué)原理，自然現(xiàn)象，則從句仍用現(xiàn)在時(shí)態(tài)。例如：The teacher told us that Tom had left us for America 5. think, believe, imagine

21、, suppose等等動(dòng)詞引起的否定性賓語從句中，要把上述主句中的動(dòng)詞變?yōu)榉穸ㄊ?。即將從句中的否定形式移到主句中。例如：We dont think you are here. 我們認(rèn)為你不在這。I dont believe he will do so. 我相信他不會(huì)這樣做。6.時(shí)態(tài)：1.主句用一般現(xiàn)在時(shí)，從句可用任意時(shí)態(tài)。2.主句用過去時(shí)，從句用過去某個(gè)時(shí)態(tài)。3.主句用過去時(shí)，從句是客觀真理時(shí)，只用一般現(xiàn)在時(shí)。7.賓語從句的連接詞從屬連詞：連接賓語從句的從屬連詞主要有that,if,whether.that引導(dǎo)表示陳述句的賓語從句,而if和whether引導(dǎo)表示“是否”的賓語從句.He tol

22、d me that he would go to the college the next year他告訴我他明年上大學(xué).I dont know if there will be a bus any more.我不知道是否還會(huì)有公交車.Nobody knew whether he could pass the exam.沒人知道他是否會(huì)通過考試.連接代詞：連接代詞主要有who, whom ,whose ,what ,whoever ,whomever ,whosever, whatever, whichever等.連接代詞一般指疑問,但what, whatever除了指疑問外,也可以指陳述.D

23、o you know who has won Red Alert game? 你知道是誰贏得了紅色警報(bào)的游戲？The book will show you what the best CEOs should know. 這本書會(huì)告訴你最好的執(zhí)行總裁該了解些什么.Have you determined whichever you should buy,a Motorola or Nokia cell phone?你決定好是買諾基亞還是摩托羅拉的電話了嗎?連接副詞：連接副詞主要有when,where,why,how,whenever,wherever,however等.He didnt tell

24、me when we should meet again.他沒有告訴我什么時(shí)候我們能再見面.Could you please tell me how you use the new panel?你能告訴我怎么用這個(gè)新的操作盤嗎?None of us knows where these new parts can be bought.沒有人知道這些的新的零件能在哪里買到.8.動(dòng)詞的賓語從句大多數(shù)動(dòng)詞都可以帶賓語從句We all expect that they will win , for members of their team are stronger.我們都預(yù)料他們會(huì)贏,因?yàn)樗麄兊年?duì)員更

25、強(qiáng)壯.He told us that they would help us though the whole work.他告訴我們在整個(gè)工作中,他都會(huì)幫忙的. 部分“動(dòng)詞+副詞”結(jié)構(gòu)也可以帶賓語從句I have found out that all the tickets for the concert have been sold out.我發(fā)現(xiàn)這場音樂會(huì)的所有票都賣光了.Can you work out how much we will spend during the trip?你能計(jì)算出這次旅行我們將花費(fèi)多少錢嗎?動(dòng)詞短語也可以帶賓語從句常見的這些詞有:make sure確保 make

26、 up ones mind下決心 keep in mind牢記Make sure that there are no mistakes in your papers before you turn them in.在上交試卷前確保沒有任何錯(cuò)誤.可運(yùn)用形式賓語it代替的賓語從句動(dòng)詞find,feel,consider,make,believe等后面有賓語補(bǔ)足語的時(shí)候,則需要用it做形式賓語而將that賓語從句后置.I think it necessary that we take plenty of hot water every day .我認(rèn)為每天多喝開水是有必要的.I feel it a

27、pity that I havent been to the get-together.我沒去聚會(huì),感覺非常遺憾.I have made it a rule that I keep diaries. 我每天寫日記成了習(xí)慣.We all find it important that we (should) make a quick decision about this mater. 我們都認(rèn)為對這件事馬上做出決定很重要. 有些動(dòng)詞帶賓語從句時(shí)需要在賓語與從句前加it這類動(dòng)詞主要有:hate, take , owe, have, see to.I hate it when they with t

28、heir mouths full of food.我討厭他們滿嘴食物時(shí)說話.He will have it that our plan is really practical.他會(huì)認(rèn)為我們的計(jì)劃確實(shí)可行.We take it that you will agree with us.我們認(rèn)為你會(huì)同意我們的.When you start the engine, you must see to it that car is in neutral.開啟發(fā)動(dòng)機(jī)時(shí), 一定要使汽車的離合器處于空擋位置.若賓語從句是wh-類,則不可用it代替 We all consider what you said to

29、be unbelievable.我們都認(rèn)為你所說的是不可信的.We discovered what we had learned to be valuable.我們發(fā)現(xiàn)我們所學(xué)到的東西都是有用的.9.介詞的賓語從句用wh-類的介詞賓語從句We are talking about whether we admit students into our club.我們正在討論是否讓學(xué)生加入我們的俱樂部.The new book is about how Shenzhou 6 manned spaceship was sent up into space.這本新書是關(guān)于神州6號(hào)載人航天飛船是如何升入太

30、空的.用that,if引導(dǎo)的介詞賓語從句有時(shí)候except,but,besides三個(gè)介詞后可見到that引導(dǎo)的賓語從句I know nothing about my new neighbor except that he used to work with a company.對于我的新鄰居我只知道他曾在一家公司上班,其他一無所知.10.形容詞的賓語從句常用來引導(dǎo)賓語從句的形容詞有: sure,certain,glad,please,happy,sorry,afraid,satisfied,surprisedI am sure I will pass the exam.我確信我會(huì)通過考試.I

31、 am sorry that I have troubled you so long.很抱歉我這么長時(shí)間在打擾你.He is glad that Li Ming went to see him when he was ill.他很高興在他生病的時(shí)候李明能去看望他.11.if,whether在賓語從句中的區(qū)別 if和whether在作“是否”解時(shí),引導(dǎo)賓語從句常放在動(dòng)詞know,ask,care,wonder,find out等之后,介詞后一般不用if 少數(shù)動(dòng)詞,如:leave,put,discuss,doubt后的賓語從句常用whether. whether后可以加or not,但是if不可以

32、. 在不定式前只能用whether.（如：I cant decide whether to stay. 我不能決定是否留下。） 避免歧異時(shí),我們常用whether而不用if.12.哪些賓語從句不可以省略引導(dǎo)詞that1.當(dāng)that作learn,suggest,explain,agree,wonder,prove,mean,state,feel,hold等動(dòng)詞的賓語時(shí);2.當(dāng)賓語從句較長時(shí);3.當(dāng)主語狀語置于主句尾,賓語從句之前時(shí);4.當(dāng)主語謂語動(dòng)詞(包括非謂語動(dòng)詞)與賓語從句之間有插入語時(shí);5.當(dāng)一個(gè)動(dòng)詞帶有兩個(gè)或兩個(gè)以上賓語從句時(shí),此時(shí)第一個(gè)that可以省略,第二個(gè)that不可以省略;6.當(dāng)

33、賓語從句中的主語是this,that或this,that做主語的定語時(shí);7.當(dāng)賓語從句是雙賓語中的直接賓語時(shí);當(dāng)賓語從句的主語是非謂語動(dòng)詞或主語從句時(shí);8.當(dāng)主語中的謂語動(dòng)詞是固定詞組時(shí);9.當(dāng)賓語從句有it做其先行詞時(shí);10.在直接引語中,轉(zhuǎn)述分句把賓語從句隔開時(shí).13.賓語從句的否定轉(zhuǎn)移主句的謂語動(dòng)詞是think,believe,imagine,suppose,consider,espect,fancy,guess等,并且主句的主語是第一人稱而且為一般現(xiàn)在時(shí),從句的否定詞一般要轉(zhuǎn)移到主句上來,其反義疑問句一般與賓語從句一致.I dont think he will come to my p

34、arty.而不能說成I think he wont come to my party.我認(rèn)為他不會(huì)來我的舞會(huì).I dont believe that man is killed by Jim,is he?我認(rèn)為那個(gè)人不是Jim所殺的,是不是?如果賓語從句中有某個(gè)含有否定意義的形容詞或副詞,其反義疑問句要用肯定形式.We find that he never listens to the teacher carefully,does he?我們發(fā)現(xiàn)他從來不仔細(xì)聽老師講課,是不是?14.賓語從句的時(shí)態(tài)和語序當(dāng)主句為現(xiàn)在時(shí)或?qū)頃r(shí),賓語從句的時(shí)態(tài)一般不受主句的時(shí)態(tài)所影響.當(dāng)主句為過去時(shí)從句用一般過去

35、時(shí)或過去進(jìn)行時(shí)表示與主句謂語動(dòng)詞動(dòng)作同時(shí)發(fā)生I only knew he was studying in a western country,but I didnt know what country he was in.我只知道他當(dāng)時(shí)在西方的一個(gè)國家讀書,可不知道是哪個(gè)國家.He asked me if I was reading the story The Old Man and the Sea when he was in.他問我他進(jìn)來的時(shí)候我是否正在讀<<老人與海>>.從句過去完成時(shí)表示該動(dòng)作發(fā)生在主句謂語動(dòng)作之前He told me that he had t

36、old Mary about the meeting already.他告訴我他已經(jīng)把有關(guān)會(huì)議的事情告訴的了Mary.從句謂語用過去將來時(shí)表示該動(dòng)作發(fā)生在主句謂語動(dòng)作之后The reporter asked if the government would take necessary measures to put down the to-do.記者問政府是否會(huì)采取必要的措施鎮(zhèn)壓騷亂.如果從句是一個(gè)客觀真理,那么從句的時(shí)態(tài)不根據(jù)主句的時(shí)態(tài)而變化The teacher said that the moon goes around the earth yesterday.老師昨天說月亮繞著地球轉(zhuǎn).

37、當(dāng)賓語從句的引導(dǎo)詞是who,which,what,when,where,how,why等表疑問時(shí),不能按正常語序安排,經(jīng)常將這類引導(dǎo)詞置于句首Who do you think the public might choose as their favorite singer this year?你認(rèn)為今年公眾會(huì)選誰為他們最喜歡的歌手. 四、表語從句1、在句中作表語的從句叫表語從句。引導(dǎo)表語從句的關(guān)聯(lián)詞與引導(dǎo)主語從句的關(guān)聯(lián)詞大致一樣，表語從句位于連系動(dòng)詞后，有時(shí)用as if引導(dǎo)。其基本結(jié)構(gòu)為：主語 + 系動(dòng)詞 + that從句。例如：The fact is that we have lost th

38、e game. 事實(shí)是我們已經(jīng)輸了這場比賽。Thats just what I want. 這正是我想要的。This is where our problem lies. 這就是我們的問題所在。That is why he didnt come to the meeting. 那就是他為什么不到會(huì)的原因。It looks as if it is going to rain. 看上去天要下雨了。需要注意的，當(dāng)主語是reason時(shí)，表語從句要用that引導(dǎo)而不是because。例如：The reason why he was late was that he missed the train by

39、 one minute this morning .【注意】whether 可引導(dǎo)表語從句，但與之同義的if卻通常不用于引導(dǎo)表語從句。2、簡介定義：A 表語從句就是用一個(gè)句子作為表語。說明主語是什么或者怎么1樣，由名詞、形容詞或相當(dāng)于名詞或形容詞的詞或短語充當(dāng)，和連系動(dòng)詞一起構(gòu)成謂語。The problem is puzzling. 這問題令人困惑主語 連系動(dòng)詞 形容詞作表語The problem is when we can get a pay rise. 問題是什么時(shí)候我們可以得到加薪.主語 連系動(dòng)詞 一個(gè)句子作表語-表語從句B 連接表語從句的連接詞有：that, what, who, w

40、hen, where, which, why, whether,how.He has become a teacher. 他已經(jīng)成為一名教師。 He has become what he wanted to be ten years ago. 他已經(jīng)成為了他10年前想成為的。She has remained there for an hour. 她曾在那里停留了一個(gè)小時(shí)。 She has remained where I stood yesterday for an hour.她一直在我昨天站的地方站了一個(gè)小時(shí)。His suggestion is good. 他的建議是好的。His sugge

41、stion is that we should stay calm. 他的建議是，我們應(yīng)該保持冷靜。The question is confusing. 這個(gè)問題令人困惑.The question is when he can arrive at the hotel. 問題是，他什么時(shí)候可以到達(dá)酒店。 who will travel with me to Beijing tomorrow.誰與我明天將前往北京。 why he cried yesterday. 昨天他為什么哭。 how I can persuade her to join us in the party. 我怎么能說服她加入我們

42、的派對。 whether the enemy is marching towards us. 是否敵人正向我們行進(jìn).注意：A 表語從句一定要用陳述語序。False: The question is when can he arrive at the hotel.Right: The question is when he can arrive at the hotel.B 不可以用if，而用whether 連接表語從句(as if 例外）。引導(dǎo)賓語從句時(shí)可以互換if/whether 位于介詞后要用whether 位于句首時(shí)要用whether 引導(dǎo)表語從句，主語從句，同位語從句時(shí)要用whethe

43、rFalse: The question is if the enemy is marching towards us.Right: The question is whether the enemy is marching towards us.Right: It looked as if he had understood this question.C 不像賓語從句，在有表語從句的復(fù)合句中，主句時(shí)態(tài)和從句時(shí)態(tài)可以不一致。Right: The question is who will travel with me to Beijing tomorrow.Right: The questio

44、n is why he cried yesterday.D that在表語從句中不可以省掉。3、基本用法表語從句只能置于主句之后，而主句的動(dòng)詞只能是聯(lián)系動(dòng)詞。名詞性從句在be等系動(dòng)詞后作表語時(shí)被稱為表語從句， 例如： The problem is how we can get the things we need.問題是我們怎樣能弄到我們需要的東西。(how 在表語從句中充當(dāng)方式狀語)/ The scissors are not what I need. 這把剪刀不是我所需要的。(what 在表語從句中充當(dāng)賓語)/ What I told him was that I would find h

45、im a good play. 我告訴他的是我會(huì)給他找個(gè)好劇本。(what在主語從句中作直接賓語， that作為表語從句的引導(dǎo)詞在該表語從句中不充當(dāng)句子成分， 不能省略)/ That is what I want to tell you.那就是我想要對你講的。(what在表語從句中充當(dāng)直接賓語)/ That is why she failed to pass the exam. 那就是她考試不及格的原因。(why 在表語從句中充當(dāng)原因狀語)注意： “That is why.”是常用句型， 意為“這就是的原因/因此”， 其中why引導(dǎo)的名詞性從句在句中作表語， 該句型通常用于針對前面已經(jīng)說明過的

46、原因進(jìn)行總結(jié)， 又如： That is why you see this old woman before you know, Jeanne. 珍妮， 這就是現(xiàn)在這個(gè)老太婆出現(xiàn)在你面前的原因。(前文提到Jeanne對老婦人顯得蒼老憔悴深感詫異， 說話人對她講述了其中的原因之后，用這一句來進(jìn)行概括)。/ That is why I came. 這就是我來的原因。下面是兩個(gè)與“That is why.”形式相似的結(jié)構(gòu)， 它們與“That is why.”結(jié)構(gòu)之間的關(guān)系要能夠辨析清楚： (1)“That is why.”與“That is the reason why.”同義， 只不過從語法結(jié)構(gòu)上講

47、， “That is the reason why.”中why引導(dǎo)的是個(gè)定語從句， 將其中的the reason去掉則與“That is why.”結(jié)構(gòu)一樣， 例如： That is (the reason) why I cannot agree. 這就是我不能同意的理由。 (2)“That is because.”句型中從屬連詞because引導(dǎo)的名詞性從句在此作表語， 這也是個(gè)常用句型， 意為“這就是為什么/因?yàn)椤??！癟hat is because.”與“That is why.”之間的不同在于“That is because.”指原因或理由， “That is why.”則指由于各種原因

48、所造成的后果， 例如： He did not see the film last night. That is because he had to help his little sister with her homework.昨天晚上他沒有去看電影， 那是因?yàn)樗脦椭拿妹米鲎鳂I(yè)。(第一句話說明結(jié)果， 第二句話說明原因)He had seen the film before. That is why he did not see it last night.他以前曾看過那部電影， 因此他昨天晚上沒有去看。(第一句話說明原因， 第二句話說明結(jié)果)五、同位語從句1、同位語從句說明其前面的名詞

49、的具體內(nèi)容。同位語從句通常由that引導(dǎo)，可用于同位語從句的名詞有advice、demand、doubt、fact、hope、idea、information、message、news、order、problem、promise、question、request、suggestion、truth、wish、word等。例如：The news that we won the game is exciting.我們贏得這場比賽的消息令人激動(dòng)。I have no idea when he will come back home. 我不知道他什么時(shí)候回來。The thought came to him

50、 that Mary had probably fallen ill. 他想到可能瑪麗生病了。同位語從句和定語從句的區(qū)別： that作為關(guān)系代詞，可以引導(dǎo)定語從句，充當(dāng)句子成分，在從句中作賓語時(shí)可以省略； that引導(dǎo)同位語從句時(shí)，起連詞的作用，沒有實(shí)際意義，不充當(dāng)句子成分，一般不能省略。 試比較下面兩個(gè)例句: I had no idea that you were here（that引導(dǎo)同位語從句，不能省略）Have you got the idea（that）this book gives you of life in ancient Greece？（that引導(dǎo)定語從句，作賓語，可以省略

51、）2、簡介同位語部分是個(gè)句子,就是同位語從句,這種用法比較"固定",把關(guān)鍵的幾個(gè)詞背下來. 一、在復(fù)合句中用作同位語的從句叫同位語從句。它一般跟在某些名詞后面，用以說明該名詞表示的具體內(nèi)容。如： I heard the news that our team had won我聽到了我們隊(duì)獲勝的消息。 I had no idea that you were here我不知道你在這里。 二、可以跟同位語從句的名詞通常有news，idea，fact，promise，question，doubt，thought，hope，message，suggestion，words（消息），po

52、ssibility等。如： Ive come from Mr wang with a message that he wont be able to see you this afternoon 我從王先生那里來，他讓我告訴你他今天下午不能來看你了。 三、英語中引導(dǎo)同位語從句的詞通有連詞 that，whether，連接副詞 how,when,where等。（注：if,which 不能引導(dǎo)同位語從句。）如： l have no idea when he will be back我不知道他什么時(shí)候回來。 He must answer the question whether he agrees t

53、o it or not. 他必須回答他是否同意這樣一個(gè)問題。 四、有時(shí)同位語從句可以不緊跟在說明的名詞后面，而被別的詞隔開。 如： Several years later，word came that Napoleon himself was coming to inspect them 幾年以后，有消息傳來說拿破侖要親自視 察他們。 The thought came to him that maybe the enemy had fled the city 他突然想起可能敵人已經(jīng)逃出城了。六、名詞性that-從句1）由從屬連詞that引導(dǎo)的從句叫做名詞性that-從句。 That只起連接主句

54、和從句的作用，在從句中不擔(dān)任任何成分，本身也沒有詞義。名詞性that-從句在句中能充當(dāng)主 語、賓語、表語、同位語和形容詞賓語，例如：主語：That she is still alive is her luck.他還活著全靠運(yùn)氣。賓語：John said that he was leaving for London on Wednesday.約翰說他星期三要到倫敦去。表語：The fact is that he has not been seen recently.事實(shí)是近來誰也沒有見過他。同位語：The fact that he has not been seen recently distu

55、rbs everyone in his office. 近來誰也沒有見過他，這一事實(shí)令辦公室所有的人不安。形容詞賓語：I am glad that you are satisfied with your job.你對工作滿意我感到很高興。2）That-從句作主語通常用it作先行詞，而將that-從句置于句末，例如：It is quite clear that the whole project is doomed to failure.很清楚，整個(gè)計(jì)劃注定要失敗。It's a pity that you should have to leave.你非走不可真是件憾事。用it作形式主語的

56、that-從句有以下四種不同的搭配關(guān)系：a. It + be +形容詞+ that-從句It is necessary that有必要 It is important that重要的是It is obvious that很明顯b. It + be + -ed 分詞+ that-從句It is believed that人們相信 It is known to all that眾所周知It has been decided that已決定c. It + be +名詞+ that-從句It is common knowledge that是常識(shí) It is a surprise that令人驚奇的是

57、It is a fact that事實(shí)是d. It +不及物動(dòng)詞+ that-從句It appears that似乎 It happens that碰巧It occurred to me that我突然想起七、名詞性wh-從句1）由wh-詞引導(dǎo)的名詞從句叫做名詞性wh-從句。Wh-詞包括who, whom,. whose, whoever, what, whatever, which, whichever等連接代詞和where, when, how, why等連接副詞。Wh-從句的語法功能除了和that-從句一樣外，還可充當(dāng)介詞賓語、賓語補(bǔ)語和間接賓語等，例如：主語： How the book will sell depends on its author.書銷售如何取決于作者本人。直接賓語：In