非限制性定语从句句型

非限制性定语从句句型

　　非限制性定语从句句型，一起来看看吧。

　　1) 定语从句有限制性和非限制性两种，限制性和非限制性定语从句。限制性定语从句是先行词不可缺少的部分，去掉它主句意思往往不明确；非限制性定语从句是先行词的附加说明，去掉了也不会影响主句的意思，它与主句之间通常用逗号分开，例如：

　　This is the house which we bought last month. 这是我们上个月买的那幢房子。（限制性）

　　The house, which we bought last month, is very nice.这幢房子很漂亮，是我们上个月买的。（非限制性）

　　2) 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，英语语法《限制性和非限制性定语从句》。

　　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。

　　3) 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。

　　说明：关系代词that和关系副词why不能引导非限制性定语从句。

　　限制性和非限制性定语从句

　　1) 定语从句有限制性和非限制性两种。限制性定语从句是先行词不可缺少的部分，去掉它主句意思往往不明确；非限制性定语从句是先行词的附加说明，去掉了也不会影响主句的意思，它与主句之间通常用逗号分开，例如：

　　This is the house which we bought last month.这是我们上个月买的那幢房子。（限制性）

　　The house, which we bought last month, is very nice.这幢房子很漂亮，是我们上个月买的。（非限制性）

　　2) 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。

　　3) 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。

　　说明：关系代词that和关系副词why不能引导非限制性定语从句。

　　附：非限制性定语从句

　　1. Everyone in our class was working hard and doing what we could _______ a good college.

　　A. enter B. to enter

　　C. entering D. entered

　　【陷阱】容易误选A。有的同学一看到空格前的情态动词 could 就断定此处应填动词原形 enter。

　　【分析】其实正确答案应是B。此句为省略句，即在 could 后省略了动词 do，若把句子补完整应为Everyone in our class was working hard and doing what we could do to enter a good college。即句中的不定式短语(to enter a good college)是用作目的状语的，而不是与情态动词(could)一起构成谓语。请再看类似例句：

　　(1) They did what they could to comfort her. 他们尽量安慰她。

　　(2) They did everything they could to save her life. 他们尽一切力量拯救她的性命。

　　(3) He studies as hard as he could to catch up with his classmates. 他拼命学习以便赶上他的同学。

　　值得指出的是，这也并不是说今后只要遇到类似结构的题就一定选带to不定式。请看以下试题：

　　(4) He ran as fast as he could _____ to catch the early bus.

　　A. to hope B. hope

　　C. hoping D. hoped

　　此题的答案是 C不是A，其中的现在分词短语 hoping to catch the early bus 用作伴随状语。

　　(5) He spent every minute he could _____ spoken English.

　　A. practise B. to practise

　　C. practising D. practised

　　此题答案选 C，这与前面动词 spent 的搭配有关，即 spend … (in) doing sth。若将此句补充完整，即为 He spent every minute he could spend in practising spoken English.

　　(6) Before going abroad he devoted all he could ____D____ his oral English.

　　A. improve B. to improve

　　C. improving D. to improving

　　此题答案选D，注意两点：一是 devote … to … 是固定搭配，意为“把……贡献给……”;二是其中的 to 是介词，不是不定式符号，后接动词时要用动名词。

　　2. He knows nothing about it, so he can’t help _______ any of your work.

　　A. doing B. to do

　　C. being doing D. to be done

　　【陷阱】容易误选B，根据 can’t help doing sth 这一结构推出。

　　【分析】其实答案应选A。比较以下结构：

　　can’t help to do sth = 不能帮助做某事

　　can’t help doing sth = 禁不住做某事，情不自禁地做某事