【正文】 雖然三者均可引導(dǎo)表語從句，但 that 沒有詞義，而 why 和 because 有自己的意思；另外，雖然 why和 because 都可引導(dǎo)表語從句，但前者強(qiáng)調(diào)結(jié)果，后者強(qiáng)調(diào)原因。The question is whether he can do 。He realized that she too was 。What he says is true, 。There’s something in what he 。英語基礎(chǔ)語法——名詞性從句一、名詞性從句的基本概念在復(fù)合句中起名詞作用的從句叫名詞性從句，包括作主語從句、表語從句、賓語從句和同位語從句。Whoever is finished may 。The reason why he is absent is that he is 。同位語從句大多由that引導(dǎo)，也可由whether, how, when, where, why等引導(dǎo)，但不能由which引導(dǎo)。：有“是否”之意，但不作句子成分；引導(dǎo)賓語從句時，還可用if。誤：I don’t know where has she ：I don’t know where she has 若主句的謂語動詞是一般現(xiàn)在時時，賓語從句的謂語動詞可根據(jù)情況使用各種時態(tài)；若主句的謂語動詞是一般過去時，其謂語動詞必須用某種過去時態(tài)。如：He said(that)the book was very interesting and that(不省略)all the children like to read ，所有小孩都喜歡讀。如： He replied that he 。如：The boy has made it clear that they can’t play with his 。2)當(dāng)主句謂語動詞的時態(tài)為過去時，從句的謂語動詞須用響應(yīng)的過去時。He told us the truth that he fell down from his bike this 。同位語從句的前面一般是數(shù)量有限的、表示抽象意義的名詞；而定語從句的先行詞是無數(shù)的指人或物名詞。同位語從句可充當(dāng)同位名詞的表語；而定語從句不能充當(dāng)先行詞的表語。主語從句學(xué)習(xí)指要用來作主語的句子叫做主語從句。如： That he was ill yesterday is known 。注意2 連接詞的選用問題A．that，whether，if，as if(限用于表語從句)都不作句子的任何成分。如：(1)Whether he will e or not doesn’t matter.—It doesn’t matter whether he will e or 。4)whether可與不定式連用，而if不可以。名詞性從句用法詳解一、概說名詞性從句，即指性質(zhì)相當(dāng)于名詞的從句，它包括主語從句、賓語從句、表語從句和同位語從句。(引導(dǎo)主語從句，不能用 if 代替 whether) who(m), whose, which, what 等，均有各自的意義，在從句中作主語、賓語、定語等。Why he did it will remain a puzzle 。注：what 后的名詞可以是復(fù)數(shù)名詞或不可數(shù)名詞，但通常不能是單數(shù)可數(shù)名詞，并且后接不可數(shù)名詞時，有時可有l(wèi)ittle修飾，兩者的區(qū)別是：what+不可數(shù)名詞=所有的都，what little+不可數(shù)名詞=雖少但全部。誤：Who es will be wele./ Anyone es will be ：Whoever es will be wele./ Anyone who es will be ，它們也可引導(dǎo)讓步狀語從句，其意為“無論?”、“不管?”，其意相當(dāng)于 no matter who [what, which]。t ，因此我沒來。, if 這兩個詞既可引導(dǎo)名詞性從句，也可引導(dǎo)狀語從句。Mary, one of the most intelligent girls I know, is planning to attend the ，她正準(zhǔn)備上大學(xué)。We girls often go to the movies 。People, old and young, took to the streets to watch the 。I received a message that she would be 。He does whatever she asks him to ，他就做什么。Whoever wants the book may have 。whichever在從句中可用作主語、賓語、定語：Buy whichever is 。Don’t lose heart whatever difficulties you 。關(guān)系型 what引導(dǎo)名詞性從句的五種用法一、用法歸納“??的東西或事情”：They’ve done what they can to help 。The young girl was too frightened to speak, standing there for what seemed like ，在那兒站了幾個小時。如：I spent what time I had with 。He didn’t tell me if [whether] he would 。【注】在很不正式的場合if偶爾也用于引導(dǎo)表語從句，但遠(yuǎn)不如用 whether 常見?！咀ⅰ咳舨皇侵苯优c or not 用在一起，則有時也可用 if：I don’t know whether [if] he will win or 。請看幾道考題：(1)______ the 2000 Olympic Games will be held in Beijing is not known [選C](2)______ we’ll go camping tomorrow depends on the [選B] 由于以上區(qū)別，所以動詞 doubt后接賓語從句時，通常要用 whether(if)來引導(dǎo)，而不用 that，因?yàn)?doubt 表示“懷疑”，其意不肯定、不明確；但是如果它用于否定式，其后的賓語從句則要通常用 that 來引導(dǎo)，因?yàn)?not doubt 表示“不懷疑”，其意是肯定的、明確的。二、時態(tài)問題由于由when引導(dǎo)的時間狀語從句和以if引導(dǎo)的條件狀語從句要用現(xiàn)在時表示將來意義，而不能直接使用將來時態(tài)，所以許多同學(xué)容易受此影響在when和if引導(dǎo)名詞性從句時也用現(xiàn)在時表示將來意義。They were worried over the fact that you were 。There was a suggestion that Brown should be dropped from the 。The question whether it is right or wrong depends on the 。He had no idea why she 。(G31)二、同位語從句與定語從句的區(qū)別 1．意義的不同同位語從句是用于說明所修飾名詞的具體內(nèi)容的，它與被修飾詞語通常可以劃等號；而定語從句是限制所修飾名詞的，它的作用是將所修飾的名詞與其他類似的東西區(qū)別開來：We are glad at the news that he will 。(定語從句)(from )We don’t understand the problem why this is the best ，為什么這是最好的選擇。The question is whether the film is worth 。That’s where I first met 。 if / as though引導(dǎo)It isn’t as if you were going away for ?！咀⒁狻縝ecause 可引導(dǎo)表語從句，但與之同義的since, as, for等也不用于引導(dǎo)表語從句。That’s because you can’t appreciate 。That’s what I want to 。The question is who(m)we should 。The trouble is that I have lost his 。如上例 that he told us中的that就充當(dāng)told的賓語。The rumour spread that a new school would be built 。隨后我回到一家工廠工作?！咀⒁?】引導(dǎo)同位語從句的連詞that通常不省略，但在非正式文體中也可以省去。He referred to Copernicus’ statement that the earth moves round the 。另外，當(dāng)主句為過去時態(tài)時，賓語從句通常要用過去的某種時態(tài)與之呼應(yīng)(表客觀真理時除外)： The teacher told us that he knew 。(from )類似地，be sure后的名詞性從句通常用that引導(dǎo)，而 be not sure 后的名詞性從句則通常用whether / if 來引導(dǎo)：I’m sure that he is 。(2)why和 because 都可引導(dǎo)表語從句，但前者強(qiáng)調(diào)結(jié)果，后者強(qiáng)調(diào)的原因：I had neither a raincoat nor an ’s why I got wet all ，也沒帶雨傘，所以全身都淋濕了。I didn’t know whether to laugh or to 。(3)以下情況通常要用 whether 而不用 if： ① 引導(dǎo)賓語從句且置于句首時：Whether he has left, I can’t ，我說不定。I believe(that)he will e to see 。正：You can have what you like./ You can have everything(that)you ：You can have everything what you like.(2)有時what 可用作限定詞，其后修飾一個名詞： I gave him what books I 。He is what is generally called a 。Whoever rings, tell him I’m ，都告訴他我不在家。(from )Whichever(of you)es in first will receive a (你們)誰先到都可以得獎。I’ll give the ticket to whoever wants ，我就把它給誰。You can have whatever allowance you 。Give them whatever they 。They neither of them wanted to 。(driving a track與a job同位)She got a place in a laundry ironing ?，F(xiàn)小結(jié)并舉例說明如下，希望引起同學(xué)們的注意。同位語邊緣知識歸納一、什么叫同位語當(dāng)兩個指同一人或事物的句子成分放在同等位置時，若其中一個句子成分是用于說明或解釋另一個句子成分的，那么用于起說明或解釋作用的句子成分就叫做另一成分的同位語。六、名詞性從句的時態(tài)問題，賓語從句若不是一個客觀事實(shí)或真理，其謂語動詞也必須用某種過去時態(tài)。(whoever = no matter who)注：whoever 既用作主格也用作賓語；作賓語時不宜用 whomever，因?yàn)樵诂F(xiàn)代英語中 whomever 這個已幾乎廢棄不用。如：Whoever wants the book may have 。I don’t know what you want is 。Tell me which one you like 。That he likes you is very 。(以上兩個句子中的whether 不能用if替換)6)賓語從句若為否定句，連接詞則用if 而不用whether。3)若用if會產(chǎn)生歧義時，則用whether。(2)I don’t know whether / if he will 。如(from )：(1)How he worked it out is still a (2)What they makes in this factory are TV 。如：(1)It is possible that he has stolen the 。表語從句中應(yīng)注意：，但當(dāng)主句中含動詞do的某種形式時，that可以省略。引導(dǎo)同位語從句的that是連詞，在從句中不擔(dān)任任何成分，但不能省略；而引導(dǎo)定語從句的that為關(guān)系代詞，在從句中擔(dān)任句子的某種成分，當(dāng)擔(dān)任定語從句中的賓語時，that可以省略?！懊睢⒔ㄗh、要求” advice, demand, decision, desire, idea, insistence, instruction, order, plan, proposal, remendation, request, requirement, suggestion, wish 等名詞的同位語，須用虛擬語氣。如(from )：Chairman Mao said that all the imperialists are paper 。Can you explain why he didn’t e to the party last Sunday? 你能解釋上周星期日他為什么沒有來參加聚會嗎？在賓語從句中須注意： 在口語中常被省略，但在正式的文體中，不能??；并且它一般不能引導(dǎo)介詞的賓語從句，但可引導(dǎo)except, but, in 等少數(shù)介詞的賓語從句。如：He has no special fault except that he smokes too ,沒有什么特別的毛病。八種賓語從句不省略that引導(dǎo)賓語從句的that在下列情況下一般不省略： 。注意：連接詞必須位于從句的最前面。注：有時，同位