名词性从句讲解(最全版)

名词性从句讲解(最全版)名词性从句是一个从句，它在句子中充当名词的角色。

它可以作为主语、宾语、表语、同位语或介词宾语。

名词性从句通常由连接词引导，如that、whether、if、who、whom、whose、which、what等。

1. 作为主语：名词性从句可以作为主语，取代一个名词或名词短语，引导词通常为that或whether。

例如：- What you said is true.（你说的是真的。

）- Whether he will come is still uncertain.（他是否会来还不确定。

）2. 作为宾语：名词性从句可以作为及物动词或介词的宾语，引导词通常为that、whether、if、who、whom、whose、which、what等。

例如：- She asked me what I wanted.（她问我想要什么。

）- I don't know if/whether he will come.（我不知道他是否会来。

）3. 作为表语：名词性从句可以作为系动词的表语，引导词通常为that、whether、who、whom、whose、which、what等。

例如：- The problem is that she doesn't understand.（问题在于她不理解。

）- The question is who will take care of them.（问题是谁会照顾他们。

）4. 作为同位语：名词性从句可以作为同位语，解释或说明前面的名词或代词，引导词通常为that、whether、who、whom、whose、which、what等。

例如：- The fact that he lied surprised me.（他撒谎的事实让我感到惊讶。

）- His belief that she will succeed is unwavering.（他坚信她会成功。

3. 连接副词：when(＝the time when什么时候，何时)，where(＝the place where什么地方，何地)，how(＝the way that/in which怎样， 以……方式，如何)，why＝the reason why为什么)。它们除起连 接作用，还在从句中作状语。
3) wh类连接词引导的主语从句： wh类连接词包括wh类的连接代词(who, whom,
whose, which, what, whoever, whomever, whichever, whatever等)和连接副词(when,
where, how, why, whenever, wherever, however 等)。what, when和wh-ever类的词有时可不表 疑问。wh类连接代词在句中既起连接作用， 又可充当主语、宾语、表语、定语等成分。 wh类连接副词在句中起连接作用，在从句中 可充当时间、地点、原因、方式状语。
【温馨提示】 ①whether/ if引导宾语从句表示“是否”
的意思时，一般情况下可互换。 ②if引导宾语从句时可以有否定式，而
whether从句则没有。 e.g. I don’t care if he doesn’t come.
5) 特殊疑问词引导的宾语从句： 由who, what, how, which, whose, where, why等词引导的宾语从句，可作动词、 介词及形容词的宾语。
【温馨提示】 doubt, doubtful与sure后名词性从句连接词 that, whether, if的选择。 ①当doubt, doubtful用于肯定句时，后面的名
词性从句的连接词常用whether或if；当 doubt, doubtful用于否定句或疑问句时，后 面名词性从句的连接词用that。

名词性从句I. !"#$%&一、定义名词性从句是在句子中起名词作用的句子。

它在复合句中能担任主语、宾语、表语、同位语，分别称为主语从句、宾语从句、表语从句和同位语从句。

二、分类&表语从句1) That is(系动词) a book.S + P 表语2) The fact is(系动词)that he has lied to usS + P 表语从句&宾语从句1) He said(vt) nothing at the meeting.S + P 宾语2) He said (vt) (that) he would help us without hesitation.S + P 宾语从句3) He is interested in (prep) what we want for breakfast.S + P 宾语从句&主语从句1) His mistakes made his teacher angry.主语+ P2) That he made so many mistakes made his teacher angry.主语从句P3)What he said made his teacher angry.主语从句P&同位语从句1) You can turn to my friend Tom for help.S + P 同位语2) The announcement that a new airport was to be built nearby made us excited.S 同位语从句+ P3) We heard the news that the war had broken out between America and Iraq.S + P 同位语从句三、引导词名称引导词在从句中担任成分连接词that, whether, if 不作成分连接代词what, whatever, who, whoever, whose, which, whichever 主语、宾语、表语、定语连接副词when, where, why, how, whenever, wherever, however 状语例如：a. He said that he would come.b. Whether he can pass the exam is not certain.c. He agrees with what I said.d. He agrees with what was said.e. I don’t know what present I should buy.f. That is where Tom used to live.g. That’s why he left.四、名词性从句语序名词性从句用陈述句语序。

4. The problem is how we can
persuade the young men to stop smoking.
5.That is why he was late.
6.That is what he is worrying about.
7.That is where he was born.
fact, news, message, idea,
suggestion, question, order, problem, belief,thought等.
引导同位语从句的连词通常有 that/whether
例:
The fact that the majority voted for the man surprised many people.
was ready.
5)介词后不能用if.
It all depends on whether they will support us.
The old woman was interested in when and where Tom and Mary had their wedding party.
5、what\who\which + ever和
no matter + what\who\which的区：
①what\who\which + ever可引导名词性 从句和让步状语从句 Whoever breaks the rule must be p unished.
Whatever you do, you must do it wel
② no matter + what\who\which只能引 导让步状语从句。如： No matter who breaks the rule, h e must be punished.