语法不是死背硬记，而是归纳演绎。我不是叫你记忆，而是教你推导。一切的名词性从句都是由五大句型推导出来的，所以我们先复习下五大句型。

主语+谓语：I do.

主语（+同位语）+谓语+宾语（+同位语）：I (your teacher) love you (my students).

主语+谓语+间接宾语+直接宾语：I give her a kiss.

主语+系动词+表语（又称：主语补足语）: You are an angel.

主语+谓语+宾语+宾语补足语：You make me happy.

名词性从句包括：主语丛句、宾语从句、表语从句和同位语从句。四种名词性从句的本质是句子分别做五大句型中的主语、宾语、表语、同位语四种成分。具体地说：五大句型中的主语换成一个句子，这个作主语的句子就叫主语从句；五大句型中的宾语换成一个句子，这个作宾语的句子就叫宾语从句；五大句型中的表语换成一个句子，这个作表语的句子就叫表语从句；五大句型中的同位语换成一个句子，这个作同位语的句子就叫同位语从句。

经研究表明，有三种句子可以变名词性从句，它们是：陈述句，一般疑问句，特殊疑问句，并且陈述句可以推导出一般疑问句（①助动词+主语+谓语？②系动词+主语+表语？），一般疑问句可以推导出特殊疑问句（特殊疑问句=疑问词+一般疑问句）。但是它们三个变名词性从句的规则却略有不同：

Ⅰ陈述句分别变主语从句、宾语从句、表语从句和同位语从句。

陈述句：QQ doesn’t have a girl friend.

变化规则：句首+that(宾从中，原则：可省略；例外：宾从并列使用不可省)

① 主语从句:That QQ doesn’t have a girl friend is a rumor.

② 宾语从句:We don’t know (that) QQ doesn’t have a girl friend.

③ 表语从句:The rumor is that QQ doesn’t have a girl friend.

④ 同位语从句:The fact that QQ doesn’t have a girl friend is rumor.

We know the fact that QQ doesn’t have a girl friend.

发现规律：that在从句中不作成份。

Ⅱ一般疑问句分别变主语从句、宾语从句、表语从句和同位语从句。

一般疑问句：Is there anything wrong with QQ? ← There is something wrong with QQ.

变化规则：第一步，变为正装语序；第二步，句首+whether/if。

原则：if只用于宾从

例外：①介词后的宾从；②放于句首宾语从句；③包含or not的名从

① 主语从句：Whether there is something wrong with QQ is a rumor.

② 宾语从句：We don’t know if/whether there is something with QQ.

③ 表语从句：The rumor is whether there is something wrong with QQ.

④ 同位语从句：The rumor whether there is something with QQ is spread.

We spread the rumor whether there is something with QQ.

发现规律：whether/if在句中不作成份。

Ⅲ特殊疑问句分别变主语从句、宾语从句、表语从句和同位语从句。

变化规则：正装语序

⑴ 特殊疑问句1：When can I become QQ’s girl friend?←Can I become QQ’s girlfriend tomorrow?← I can become QQ’s girlfriend tomorrow.

① 主语从句：When I can become QQ’s girl friend is a question.

② 宾语从句：I don’t know when I can become QQ’s girl friend.

③ 表语从句：The question is when I can become QQ’s girl friend.

④ 同位语从句：The question when I can become QQ’s girl friend is puzzling.

I want to forget the question when I can become QQ’s girl friend.

发现规律：when/where/why/how在从句中作状语。

⑵ 特殊疑问句2：Which/whose girl is QQ’s girl friend? ← Is QQ’s girl friend FuRong? ←QQ’s girl friend is FuRong.

① 主语从句: Which/whose girl QQ’s girl friend is is a question.

② 宾语从句: We don’t know which/whose girl QQ’s girl friend is.

③ 表语从句: The question is which /whose girl QQ’s girl friend is.

④ 同位语从句: The question which /whose girl QQ’s girl friend is is puzzling.

I want to forget the question which /whose girl QQ’s girl friend is.

发现规律：which/whose在从句中作定语，后面常常跟名词。

⑶ 特殊疑问句3： Whom will QQ marry? ← Will QQ marry FuRong?← QQ will marry FuRong.

① 主语从句: Whom QQ will marry is a problem.

② 宾语从句: We don’t know whom QQ will marry.

③ 表语从句: The problem is whom QQ will marry.

④ 同位语从句: The question whom QQ will marry is puzzling.

I want to forget the question whom QQ will marry.

发现规律：whom在从句中作宾语。

再给大家两个特殊疑问句作为练习，大家把这两个句子用我们上述变化规则分别变为主语从句、宾语从句、表语从句和同位语从句，变化后再看看who和what分别在从句中作什么成份。

⑷ 特殊疑问句4：Who can become W’s girl friend?

⑸ 特殊疑问句5：What is the result of this marriage?

通过以上的讲解和练习，我们会发现如下两条规律：

⑴ 名词性从句万变不离其“宗”——变化规则；

⑵ 无论主句还是从句都有共同的基础——五大句型。

纷繁复杂的名词性从句我已经给大家归纳讲解了，剩下的工作就是大家通过重复复习刻苦练习在阅读与写作的一瞬精彩演绎！