非限制性定语从句
非限制性定语从句
非限制性定语从句
非限定性定语从句：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
eg:
Her house,which was built a hundred years ago,stood still in the earthquake.
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。
eg： Charles Smith, who was my former teacher, retired last year.
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， eg： 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。
总结：非限制性定语从句只是对主句内容，或先行词的补充、解释或附加说明。主句与先行词或从句之间一般用逗号分开，常常单独翻译。没有它，主句意思仍然完整。引导非限制性定语从句的关系代词有as，which，who， whom，whose等，作定语从句的主语、宾语、表语及定语。关系副词有when，where等，作定语从句的状语。关系代词和关系副词在定语从句中一般不能省。
注：why不能引导非限制定语从句
My success in business,the reason why he dislikes me（限制性）,has been due to hard work.
限制性定语从句和非限制性定语从句
限制性定语从句举例：
(1)The teacher told me that Tom was the only person that I could miss.
(2)China is a country which has a long history.
非限制性定语从句举例：
(1)His mother, who loves him very much, is strict with him.
(2)China, which was founded in 1949, is becoming more and more powerful.
限制性定语从句和非限制性定语从句区别：
要注意区分以下几个句子的不同
(1)His brother who is now a doctor always encourages him to go to college.
他那当医生的哥哥常鼓励他要考上大学。（他还有其他的哥哥）
(2)His brother, who is now a doctor, always encourages him to go to college.
他的哥哥是当医生的，常鼓励他要考上大学。（他只有一个哥哥）
介词+关系代词引导的定语从句
关系代词在定语从句中做介词宾语时，从句常由介词+关系代词引导
(1)The school (that/which) he once studied in is very famous.
=The school in which he once studied is very famous.
(2)Tomorrow I will bring here a magazine (that/which) you asked for.
=Tomorrow I will bring here a magazine for which you asked.
(3)We’ll go to hear the famous singer (whom/that/who) we have often talked about.
=We’ll go to hear the famous singer about whom we have often talked.
注意：1、有些动词短语一般不拆开使用，如：look for, look after, take care of等
(1)This is the watch which/that I am looking for. （True)
(2)This is the watch for which I am looking. (False)
2. 若介词放在关系代词前，关系代词指人时用whom，不可用who或者that；指物时用
which，不能用that；关系代词是所有格时用whose
(1) The man with whom you talked is my friend. (T)
(2) The man who/that you talked with is my friend. (F)
(3) The plane in which we flew to Canada is very comfortable. (T)
(4) The plane in that we flew to Canada is very comfortable. (F)
3、“介词+关系代词”前可有some, any, none, both, all, neither, most, each, few等代词或者数词 (1) He loved his parents deeply, both of whom are very kind to him.
