二、句型剖析

1.that引导主语从句

【典型例句】

That the earth turns around the sun is known to all.

地球绕着太阳转这一点是众所周知的。

That it will rain this afternoon is certain.

今天下午一定会下雨。

【相关链接】

(1)that引导主语从句时，为了平衡句子结构，常常用it来作形式主语。

It is reported that three people were killed in the traffic accidents.

据报道，那次交通事故中有3人丧命。

It happened that I didn't take any money with me.

碰巧我身上没带钱。

(2)what引导主语从句与that引导主语从句的区别：这两者最根本的区别在于what要在从

句中作成分，有意义，而that引导主语从句时，that不作成分，没有具体意义。

What you said was right.

(what作said的宾语)

It was thought that you are right.

(that不作成分)

(3)引导主语从句的that不可省略。

2.which引导非限定性定语从句。

【典型例句】

He lives in Beijing, which is the capital of China.

他住在中国的首都，北京。

He gave me a book, which is very interesting.

他给了我一本很有趣的书。

He turned out to be very successful, which was more than we could expect.

出乎我们的意料，他成功了。

【相关链接】

关系代词as和which都能引导非限定性定语从句，用来指代修饰整个句子，其区别如下：

(1)as引导的定语从句可放在主句前，也可放在主句后，意为"正如；正像"，从句的谓

语动词多是see, know, expect, say, mention, report, announce等。

(2)which引导的非限定性定语从句只能放在主句之后，意为"这一点"。

As is known to all, he is an honest person.

He is an honest person, as is known to all.

众所周知，她是一个诚实的人。

He was late for school again, which made the teacher very angry.

他又一次迟到了，这件事使老师很生气。