宾语从句是对动词后的代词进行补充说明
e.g.He thinks it (a good job that he becomes a teacher.)括号里就是补充内容
定语是对名词进行修饰,定语从句通常出现在先行词之后,由关系词(关系代词或关系副词)引出
e.g. She is the girl who sings best of all.
状语从句主要用来修饰主句或主句的谓语
e.g. I didn’t realize how special my mother was until I became an adult.
非限定性定语从句的作用是对所修饰的成分作进一步说明,通常和主句间用逗号隔开,将从句拿掉后其他部分仍可成立。
1. which引导的非限定性定语从句来说明前面整个句子的情况或主句的某一部分 ,that不能用于引导非限制性定语从句
例如:
Her house,which was built a hundred years ago,stood still in the earthquake.(那座房子在地震中依然耸立,它是一百多年前建造的。)
2. 有时as也可用作关系代词
3. 在非限定性定语从句中,用who, whom代表人,用which代表事物。
4.当先行词是专有名词或物主代词和指示代词所修饰时,其后的定语从句通常是非限制性的。
例如:
Charles Smith, who was my former teacher, retired last year. 查理·史密斯去年退休了,他曾经是我的老师。
My house, which I bought last year, has got a lovely garden. 我去年买的的那幢房子带着个漂亮的花园。
This novel, which I have read three times, is very touching. 这本小说很动人,我已经读了三遍。
5.非限制性定语从句还能将整个主句作为先行词, 对其进行修饰, 这时从句谓语动词要用第三人称单数,
例如:
He seems not to have grasped what I meant, which greatly upsets me. 他似乎没抓住我的意思,这使我心烦。
Liquid water changes to vapor, which is called evaporation. 液态水变为蒸汽,这就叫做蒸发。
参考资料:http://baike.baidu.com/view/576409.htm?fr=ala0_1
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