名詞性從句包括主語從句，賓語從句、同位語從句和表語從句，這幾類從句用法復(fù)雜、學(xué)習(xí)難度較大，學(xué)員在考試中丟分現(xiàn)象嚴(yán)重。

　　一、考點聚焦

　　1、名詞性從句中連接詞的運用名詞性從句中的連接詞有連詞that / whether / as if，連接代詞what / who/ which / whose / whatever / whoever / whomever / whichever，連接副詞where / when / why / how / wherever / whenever.

　　（1）that的用法。

　�、僦髡Z從句、表語從句、同位語從句中用that但不能省略。如：

　　That they are good at English is known to us all.

　　The problem is that we don't have enough money.

　　She expressed the hope that they would come to China one day.

　　②賓語從句中的連接詞that有時可省有時又不可省，在以下幾種情況中that不能省略：

　�。ˋ）當(dāng)that從句和主句謂語動詞之間有插入詞語或者從句主語之間有插入語時，that不可省略；

　�。˙）當(dāng)that 從句與另一名詞性從句并列作賓語時，that不能��；（C）當(dāng)that作介詞賓語時，that不可省掉。如：

　　Everyone knew what happened and that she was worried.

　　The reason lies in that she works harder than the others do.

　�、� that從句作主語和賓語時，可以用it 來替換成以下幾種結(jié)構(gòu)表達(dá)。

　　（A）It is clear/certain/likely/true/surprising that… （B）It is a pity/shame/good idea/no wonder that ……（C）It is said/reported/ believed/known/thought/suggested that … （D）It seems/happens that.如：

　　It happened that I went out last night.

　　It is said that China will win in the World Cup.

　�、躷hat和what的區(qū)別。

　　that 引導(dǎo)名詞性從句時，在主從句中不以當(dāng)任何句子成分，也沒有任何含義；而what引導(dǎo)名詞性從句時，在主從句中都要充當(dāng)一定的句子成分，what可以分解成定語從句中的先行詞 + 關(guān)系代詞即常說的先行詞 + that.如：

　　It's shame that he has made such a mistake. Do what he says.

　�、萃�位語從句與定語從句中that的區(qū)別。

　　同位語從句中的連詞that只起連接作用，在從句中不擔(dān)當(dāng)任何句子成分；而定語從句中的關(guān)系代詞that在句中做賓語或主語，賓語與先行詞有修飾關(guān)系。如果句子是同位語從句，就應(yīng)用連詞that而不能用which.同位語從句一般放在表具體含義的名詞后解釋名詞的含義或內(nèi)容，如以下名詞：news、fact、suggestion、truth、plan、belief、doubt、possibility、idea等，而定語從句只是對先行詞的限定和修飾。如：

　　They expressed the hope that they would come to visit China again.（同位語從句）

　　The hope she expressed is that they would come to visit China again.（定語從句）

　�。�2）whether和if的用法。

　　①whether和if在賓語從句中可以互換，但是作介詞賓語時連接詞一般用whether.如：It all depends on whether they will come back.②后面直接跟or not 時用whether.如：I didn't know whether or not he had arrived in Wuhan.③主語從句表語從句中只能用whether.如：Whether the meeting will be put off has not been decided yet.The question is whether they have so much money.④whether可以引導(dǎo)同位語從句，用以說明前面的名詞的內(nèi)容，if不能。如：We ought to discuss carefully the question whether we can do it or not.⑤whether常與or連用表示一種選擇，if不能這樣用；whether也可與動詞不定式連用但if不能。如：The question of whether they are male or female is not important.

　　I have not decided whether to go or not.⑥間接引語位于句首時或者是間接引語提前時用whether不用if.如：Thank you, but whether I'll be free I'm not sure at the moment.⑦whether可引導(dǎo)一個讓步狀語從句表示

　　“不管”、“無論”，而if不能。如：Whether he comes or not, we will begin our party on time.

　　（3）疑問詞 + ever和no matter + 疑問詞的區(qū)別。①疑問詞 + ever可引導(dǎo)名詞性從句，在主從句中要充當(dāng)一定的部分。如：Whoever breaks the rule must be punished.You can choose whatever you like in the shop.②疑問詞 + ever還可引導(dǎo)讓步狀語從句。如：Whoever breaks the rule, he must be punished,Whatever you do, you must do it well.③no matter + 疑問詞只能引導(dǎo)讓步狀語從句。如：No matter what you do, you must do it well.No matter who breaks the rule, he must be punished.

　�。�4）when和where引導(dǎo)的同位語從句與定語從句的區(qū)別。when 和where前面的名詞若是表示時間、地點的名詞，則when和where引導(dǎo)的是定語從句，否則則為同位語從句。如：They put forward the question where they could get the money.

　　This is the place where the accident happened.

　　2、名詞性從句中主句和從句的時態(tài)一致

　�。�1）賓語從句中主句和從句的時態(tài)保持一致，但如果從句中表示提示的是客觀現(xiàn)象，雖然主句是過去時態(tài)，從句仍用一般現(xiàn)在時。如：

　　Hello,I didn't know you were in London. How long have you been here?

　　The teacher told us that light travels at a very high speed.

　�。�2）主語從句作主語相當(dāng)于單數(shù)第三人稱作主語，謂語動詞用單數(shù)，如果由and 連接兩個或兩個以上的主語從句作主語時，謂語動詞用復(fù)數(shù)；由兩個或多個連接詞引導(dǎo)一個主語從句，謂語動詞用單數(shù)。如：

　　When the meeting will begin has not been decided yet.

　　When they will start and where they go have not been decided yet.

　　When and where the meeting will begin has not been decided.

　　3、名詞性從句的詞序

　　名詞性從句在句中要用陳述句語序。如：

　　He asked me what was the matter with me.

　　We've heard the news that we'll move into the new house.

　　Whatever you say will interest us all.

　　二、精典名題導(dǎo)解

　　選擇填空1. A computer can only do ________ you have instructed it to do.

　　A.how

　　B.after

　　C.what

　　D.when解析：答案為C.本題考查的是名詞性從句作賓語的用法。此句的引導(dǎo)詞既作連詞又在賓語從句中充當(dāng)一成分，故what最合適。

　　2. ―I drove to Zhuhai for the air show last week……

　　―Is that _________ you had a few days off ?

　　A.why

　　B.when

　　C.what

　　D.where解析：答案為A.此題考查的是從句的用法。根據(jù)題意“我上周開車去珠�？春娇照谷チ�。”下面一句接著問：“那就是你為什么離開的原因嗎？”故用why引導(dǎo)表語從句表示原因。

　　3. I hate __________ when peope talk with their mouths full.

　　A.it

　　B.that

　　C.these

　　D.them解析：答案為A.本題考查的是形式賓語的用法。題意為“我討厭人們談話時嘴里塞滿東西”。該空白處沒有任何含義，而且已經(jīng)用了when連接該賓語從句，所以此處只填一個形式賓語it.