1、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 didnt
2、 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
3、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。
