名词性从句从句有名词性从句、定语从句和状语从句三大类。

名词性从句又可分为宾语从句、表语从句、主语从句及同位语从句，因为从句的在这个句子中的功用相当于名词；定语从句有称为形容词性从句，因为从句功能相当于形容词；而状语从句则称为副词性从句，因为从句功能相当于副词。

什么是名词性从句?在英语的句子结构中，本来该由名词充当的主语、宾语、表语和同位语，由一个句子来充当,这个句子就叫名词性从句。

宾语从句( The Object Clause)表语从句( The Predicative Clause)主语从句( The Subject Clause)同位语从句( The Appositive Clause)表语从句一．定义在句中充当表语的从句(即放在be动词后面)叫做表语从句。

二．构成一般结构是“主语＋关联词＋表语从句”。

Our purpose is that he can realize his faults.我们的目的是他能认识到错误。

注意：引导表语从句的连接词一般不省略。

问题是它是否值得做。

注意：表语从句表示“是否” 只用“whether” 而不用“if”。

三．引导表语从句的关联词的种类1. 可接表语从句的连系动词有be，look，seem，sound，appear等。

China is no longer what she used to be.今日的中国不再是过去的中国了。

At that time，it seemed as if I couldn't think of the right word.当时，我似乎怎么也想不出一个恰当的字眼来。

2. 从属连词whether，as，as if / though引导的表语从句。

He looked just as he had looked ten years before.他看起来还与十年前一样。

It sounds as if someone is knocking at the door.听起来好像有人在敲门。

3. because，why引导的表语从句。

That's because he didn't understand me.那是因为他没有理解我。

（That's because…强调原因）That's why he got angry with me.那正是他对我生气的原因。

（That's why…强调结果）注意：what引导的主语从句表示结果或名词reason作主语时，后面的表语从句表示原因时要用that引导，不宜用because.The reason why I was sad was that he didn't understand me.我难过的原因是他没有理解我。

4. 连接代词who，whom，whose，what，which，whoever，whatever，whichever连接副词where，when，how，whyThe problem is who we can get to replace her.问题是我们能找到谁去替换她呢。

The question is how he did it.问题是他是如何做此事的。

That was what she did this morning on reaching the attic.那就是她今晨上了阁楼干的。

5. 从属连词thatThe trouble is that I have lost his address.麻烦是我把他的地址丢了。

6. 使用虚拟语气的表语从句在表示建议、劝告、命令含义的名词后的表语从句，谓语动词需用“should+动词原形” 表示，should可省略。

常见的词有：advice，suggestion，order，proposal，plan，idea等。

My suggestion is that we （should）start early tomorrow.我的建议是我们明天一早就出发。

四．应注意的问题：1. 连系动词be，appear，seem，look等之后可以跟表语从句。

It was because he didn't pass the exam.那是因为他没有通过考试。

It seems（that）he was late for the train.看来他没搭上火车。

It appears that she was wrong.看来她错了。

It seems to me that we should answer for this.在我看来，我们似乎应该对此事负责。

It appears to her that he wants to teach us all he has.在她看来，他似乎要把他所会的都教给我们。

2. 引导表语从句的引导词有以下几类。

1）wh-疑问词My question is who left.我想问的是谁离开了。

What I wonder is when he left.我想知道他是何时离开的。

That's what he wants.那是他想要的。

This is where they once lived.这就是他们曾经住过的地方。

That is why he didn't come here. 这就是他为何没到这儿来的原因。

2）whetherMy question is whether he left（or not）。

我的问题是他是否离开了。

注：if不能引导表语从句。

3）thatThe fact is that he left. 事实是他离开了。

注：引导表语从句的连词that间或可以省略。

The truth is（that）I didn't go there. 事实是我没去那儿。

4）because，as，as if，as thoughIt's just because he doesn't know her. 这是仅仅因为他不认识她。

Things are not always as they seem to be. 事物并不总是如其表象。

He looks as if he's tired. 他好像累了。

高考回顾［考题1］The traditional view is ____ we sleep because our brain is “programmed” to make us do so. (2007上海)A. whenB. whyC. whetherD. that［答案］D［解析］下划线处之后是包含一个原因状语从句的表语从句，如果看不出它是充当整个句子结构的表语从句将难以把握整个句子的意思。

因此，应选择可引导名词性从句且不充当任何成分的that。

［考题2］You are saying that everyone should be equal, and this is ____ I disagree. (2004)A. whyB. whereC. whatD. how［答案］B［解析］下划线处的引导词引导系动词is后的表语从句并在该表语从句中充当地点状语(“disagree”属于不及物动词，“I disagree”本身是完整的主谓结构)，下划线应填入引导词where，表语从句“where I disagree”的意思是“我不同意之处、我不同意的地方”。

［考题3］— I drove to Zhuhai for the air show last week.— Is that ____ you had a few days off? (1999)A. whyB. whenC. whatD. where［答案］A［解析］下划线处的引导词引导与系动词is连用的表语从句并在该表语从句中充当原因状语，下划线应填入表示“因此……”(指因某种原因所造成的结果)的引导词why。

［考题4］____ she couldn’t understand was ____ fewer and fewer students showed interest in her lessons. (2000上海)A. What; whyB. That; whatC. What; becauseD. Why; that［答案］A［解析］第一个下划线处的引导词引导主语从句并在该主语从句中充当宾语，特指她所不理解的事情，应填入关系代词型的引导词what；第二个下划线处表示“因此……”(指因某种原因所造成的后果，由why引导对应的名词性从句)而不是“为什么……”(指原因、理由，由because引导对应的名词性从句)，应填入引导词why。

［考题5］____ made the school proud was ____ more than 90% of the students had been admitted to key universities. (2003上海春)A. What; becauseB. What; thatC. That; whatD. That; because［答案］B［解析］第一个下划线处的引导词引导主语从句并在该主语从句中充当主语，特指令校方骄傲的事情，应选用关系代词型的引导词what；第二个下划线处引导表语从句表示原因、理由，应由that 引导对应的名词性从句。

［考题6］—Are you still thinking about yesterday’s game?—Oh, that’s ____. (2003北京春)A. what makes me feel excitedB. whatever I feel excited aboutC. how I feel about itD. when I feel excited［答案］A［解析］A选项的意思是“令我感觉激动的事物”；B选项的意思是“我觉得激动的任何事物”；C选项的意思是“我对它感觉的方式”；D选项的意思是“令我感觉激动的时间”。

四个选项中A最适合跟代表“game”的主语that对应，充当表语从句。

牛刀小试( ) 1. The question is ________ we will have our sports meet next week.A. thatB. ifC. whenD. whether( ) 2．The reason why he failed is ________he was too careless.A. becauseB. thatC. forD. because of( ) 3. Go and get your coat. It’ s ________you left itA. whereB. thereC. there whereD. where there ( ) 4．The problem is _________to take the place of TedA. who can we getB. what we can getC. who we can getD. that we can get ( ) 5. What I want to know is ______ he likes the gift given by us.A. thatB. ifC. whetherD.不填( ) 6. The reason is _________I missed the bus.A. thatB. whenC. whyD. what( ) 7. That is __ ___ we were late last time.A. thatB. whenC. whyD. what( ) 8. She looked _________ she were ten years younger.A. thatB. likeC. asD. as though( ) 9.—I fell sick!--I think it is _______ you are doing too much.A. whyB. whenC. whatD. because( )10. The reason why he hasn’t come is ___________.A. because his mother is illB. because of his mother’s being illC. that his mother is illD. for his mother is ill( )11. —He was born here.-- That is _______ he likes the place so much.A. thatB. whatC. whyD. how( )12.That is ______ Lu Xun once lived.A. whatB. whereC. thatD. whythat/what的区别1．_______your father wants to know is________ getting on with your studies.A. What; how are youB. That；how you areC. How；that you areD. What；how you are2. The trouble is__________we are short of tools.A. whatB. thatC. howD. why that3. America was __________was first called “India” by Columbus.A. whatB. whereC. the placeD. there where4. China is becoming stronger and stronger. It is no longer_________ .A. what it used to beB. what it was used to beingC. what it used to beingD. what it was used to be5. ________he really means is ________he disagrees with us.A. What … thatB. That … whatC. What … whatD. That … what6. The energy is ________ makes the cells able to do their work.A. thatB. whichC. whatD. such高考练习1 —I drove to Zhuhai for the air show last week .—Is that_____ you had a few days off？（NMET1999）A. why B .what C. when D. where2 .I had neither a raincoat nor an umbrella ______I got wet through. （1998·上海）A. It’s the reasonB. That’s whyC. There’s whyD. It’s how3. See the flags on top of the building? That was ______ we did this morning. （06 全国）A. whenB. whichC. whereD. what4. --- Are you still thinking about yesterday’s game?(2003北京春)---Oh, that’s _____.A. what makes me feel excitedB. whatever I feel excited aboutC. how I feel about itD. when I feel excited5. What surprised me was not what he said but ______ he said it.（2004湖北）A. the wayB. in the way thatC. in the wayD. the way which答案DBACCACDDCCBthat/what的区别DBAAAC高考练习ABDAA。