名词从句在整个句子中充当名词，既然是名词，那么在句子中，可以为主语、宾语、补语、同位语。
名词子句的种类
- 直述句改造而来的名词子句
- 疑问句改造而来的名词子句
直述句
该子句一般用无意义的从属连接词that(表示【那句话】或【那件事】)引导,当做名词使用
I believe that he didn’t take the money
疑问句
1.来自Information Question
疑问词(who、which、what、when、why、how、where等)引导的疑问句，称为Information Question.这种疑问句，疑问词可以充当从属连接词，不必加任何东西就可以直接成为名词子句。
I never asked him
what happened at his party.该名词子句在句子中充当宾语补语
再看一个不一样的例子
Where did he keep the money?
where在这个句子中是作为副词使用的，而不是名词
He never reveal
where he keep the money.在子句中，where同样是副词，而不是名词主语
2.Yes/No Question
如果疑问句中并没有疑问词,这种疑问句称为Yes/No Question,它要改成名词子句的话必须要加上从属连接词whether或if.
By looking at the sky,I can tell
whether it is going to rain(or not).
关于whether和if的使用场景：
句首只能用whether
Whether we can win the big prizewill be decided soon.介系词后面可以用whether
The manager hinted at
whether he would sign the conract.
名词子句的位置
名词子句必须放在主要子句中当做名词使用。
名词的位置有如下5种：
- 主词
- 动词的受词
- 补语可能是名词
- 名词的同位格
- 介系词的受词
在直述句改为名词子句时，that一般可以省略，如子句太长，太复杂，可以加上，明确结构。
一、主词位置
- That 子句
That the suspect has a strong alibiis an undeniable fact.
注意:这里的that不能省略
在这里，从属子句比较长，对于这种情况，一般将名词从句移动到句尾，而句首的主词位置则用虚词it代替
It is an undeniable fact that the suspect has a strong alibi.
这样写句子结构就比较清楚
- Wh-子句
Where he is hiding now is a big mystery.
改进:It is a big mystery where he is hiding now.
这里where作为连接词是有意义的，不能省略
二、动词的受词位置
- That 子句
Many people believe
that one's zodiac sign determine's one charater.
在S+V+O+C句型中，如果此时O是名词子句，但是后面还有补语C，会造成句意不清楚，所以，一般用虚词it暂时代替，将名词子句移动到句尾。
I find it amazing
that you still look so young.
- Wh-子句
He explained
why he had bought so much of that stock.why是有意义的链接词，不可省略
三、补语位置
- That 子句
It seems that we’re going to win this game after all.
- Wh-子句
The question is
whether we can do anything about it.whether解释为是否，有意义，不可省略
四、同位格位置
- That 子句
可以暂时将同位格理解为，名词后面再加上一个名词，那么这两个名词的意义是一样的
The woman can’t forget the fact
that her huaband cheated on her.
- Wh-子句
The question
why the dinosaurs died outmay never be answered.
五、介系词的受词位置
介系词后面需要受词，但是不能是直述句加that构成的名词子句，一般是wh-引导的名词子句
My response depends on what he really meant by that.
一种可行的改编，利用同位格
His response dwells on the fact
that I owe him a favor.
评论子句
如you know,I guess等，一般放在句子中做补充说明
He was really afraid,I believe.
This trick,you know,will never work.
