//本篇为《英语语法新思维中级教程——通悟语法》第二章“名词从句”的读书笔记。
English is important is an undoubted fact.
That English is important is an undoubted fact.
句1中，English is important is an undoubted fact. 有两个中心谓语 is important 和 is an undoubted fact，令人混淆。
在英文中，句子的核心意思主要是靠谓语部分来表达，一个句子只表达一个核心意思。引导词相当于一个指路牌，标志着该引导词后接的内容不是要表达的核心意思。
引导词：that, whether/if, what/when/why/which/where/how
本篇结构如下：
1. 名词从句
2. 主语从句
3. 宾语从句
4. 表语从句
5. 同位语从句
一、名词从句
对于名词从句的解释：
1. 用先行词引导一个陈述句，这个从句可以看作一个名词。如果去掉从句，则句子成分不完整。
2. 用“三种句子”作另一个句子的“四种成分”。
三种句子：(1) 陈述句 (2)特殊疑问句 (3)一般疑问句
四种成分：(1)主语 (2)宾语 (3)表语 (4)同位语
3. “三种句子”作句子成分的格式
a) 陈述句作句子成分：“that+陈述句”
b) 一般疑问句作句子成分：“whether/if + 陈述语序”
// whether/if 翻译为“是否”，表示原句中的疑问意义。
// if引导的从句只能用于宾语从句，whether不受限制
c) 特殊疑问句作句子成分：“疑问词 + 陈述语序”
二、主语从句
“三种句子”分别作句子的主语。
a)陈述句
That the seas are being overfished has been known for years.
主句缺少主语：____ has been known for years.
从句：that + (陈述句) the seas are being overfished
It has been known for years that the seas are being overfished.
主语从句更常见的形式：“It is + 过去分词/形容词/名词短语 + that + 从句”
b)一般疑问句
Whether he comes or not makes no difference to me.
主句：____ makes no difference to me. 缺少主语
从句：whether + (陈述句) he comes or not
// whether or not / whether...or not 都正确
// if or not(错)，if...or not(正确)
c)特殊疑问句
What we need is wholly new kind of police force.
How a person masters his fate is more important than what his fate is.
主句：____ is wholly new kind of police force. 缺少主语
从句：what + (陈述句)we need. 将原本的倒装句 What do we need? 调整为陈述句语序。
句2同理。
三、宾语从句
“三种句子”分别作句子的宾语。
*从句作宾语可以省略引导词that
* if 只能引导宾语从句，whether不受限制
a)陈述句
We know (that) the world is round.
主句：We know ____. 缺少宾语
b)一般疑问句
I don’t know if/whether he needs my help.
I don’t know if he comes or not.
// whether or not / whether...or not 都正确
// if or not(错)，if...or not(正确)
c)特殊疑问句
I have not decided whom I should vote for.
Could you tell me where the post office is?
They gave who came to the meeting a pamphlet.
四、表语从句
“三种句子”分别作句子的表语。
*表语从句的标志：主语 + be动词(am/is/are) + 从句
*宾语从句：主语 + 动词(行为) + 从句
a)陈述句
My idea is that the child should be sent to school.
b)一般疑问句
My concern is whether he comes or not.
c)特殊疑问句
Money is what we are badly in need of.
五、同位语从句
同位语从句，作用是补充说明名词。
结构：“名词 + 连词 + 同位语从句”
例句中
example
表示被从句修饰的名词
a)陈述句
The factthat he succeeded in the experiment pleased everybody.
b)一般疑问句
They are faced with
the problemwhether they should continue to work.
c)特殊疑问句
I have no
ideawhen he will return.
总结
* “引导词+陈述语序”构成一个名词从句
* 名词从句中，若取出从句，则句子成分不完整。定语从句中，取出从句，句子成分仍旧完整。
判断一个句子作 主语/宾语/表语/同位语从句 的标志：
* 主语从句：(1) That + 陈述句 + 主句 (2) It is ~ that + 从句
* 宾语从句：主语 + 动词 + 从句
* 表语从句：主语 + be + 从句
* 同位语从句对一个名词进行补充说明：名词 + 连词 + 同位语从句