2018年公共英语三级语法学习技巧：定语从句
定语从句
1. 定语从句又被称为形容词性从句或关系从句，其实质是修饰名词或代词的主谓结构，被修饰的名词或代词叫先行词。
2. 连接名词(代词)和定语从句的关联词称为关系词，有关系代词和关系副词，掌握定语从句的关键在于掌握关系词的用法。
3. 定语从句分为限定性定语从句和非限定性定语从句。限定性定语从句是主句意思不可缺少的部分，如果把它去掉，主句的意思便难以完整。非限定性定语从句只对作修饰的词作进一步的说明，它是一种插入语，旁白或注释，如果把它删去，主句的意思仍然完整。非限定性定语从句与先行用逗号隔开。
例如：You may select the one which is most to your taste. (限定性定语从句)
That man, whose work is important, has been a teacher.(非限定性定语从句)
(一)由关系代词引导的定语从句
经典考题
1. The few points the president stressed in his report are very important.
A) which B) who C) as D) where
2. All is a continuous supply of the basic necessities of life.
A) what is needed B) for our needs
C) the thing needed D) that is needed
考点分析
1)能引导定语从句的关系代词有：who (whom ,whose )、which 和 that。其中，who ( whom, whose )指人，which 指物，that 既指人，也指物，例如：
The woman who (that )is speaking at the meeting is a famous writer.
The train which (that ) has just left is a new one.
2) 注意关系代词that 的使用：当① 先行词前有限定词(all、any 、every、no等)、序数词、形容词最高级时;② 先行词本身是限定词或不定代词(nothing、 everything、anything等)时;③ 先行词是既指人又指物的并列名词时，必须使用关系代词that。如：I like the people and the places that I visited in Beijing last year.
3) 关系代词除连接句子外，一般在从句中作主语、宾语或定语。
答案:1. A 2.D
(二) 由关系副词引导的定语从句
经典考题
1. The day will come soon China will become a modern, powerful, socialist country.
A) when B) before C) since D) as
2. The village I once worked has taken on a new look.
A) which B) where C) when D) that
考点分析
1)能引导定语从句的关系副词有when(= at which )、where (= in which )和 why(= for which ),它们既可引导限定性定语从句，也可以用来引导非限定性定语从句，如:That is the reason why I did it.
2) 关系副词引导的定语从句可以与其先行词分开，中间由谓语隔开，有的语法书称之为割裂修饰，其目的是为了求得句子的平衡。如：The time has come when ordinary people can use computers.
3) 关系副词除连接定语从句外，一般在从句中作状语成分。
答案:1. A2.B
(三)带介词的定语从句
经典考题
1. We need a chairman .
A) for whom everyone has confidence B) in whom everyone has confidence
C) who everyone has confidence of D) whom everyone has confidence on
考题分析
引导定语从句的关系代词可以作介词的宾语，形成带介词的定语从句，这种结构有两种：
1)从句由“介词+ which (表示事或物)或“介词+whom”(表示人)构成。
如：The man to whom he is talking is our president.
The school in which I studied is a famous university.
2) 从句由“名词(或代词)+of + which(或whom)”构成。
如：The citizens, most of whom were workers, welcomed the new law.
Mt. Tai, the summit of which is hardly seen, is often covered with snow.
答案:1. B
解题要诀
掌握常用介词的基本用法。
掌握常用的动词、形容词与介词之间的固定搭配，这是解题的关键。
(四)非限定性定语从句
经典考题
1. Helen was much kinder to her youngest child than she was to the others， ____ of course, made the others jealous.
A) who B) that C) what D) which
考点分析
能引导非限定性定语从句的关系词有：who (whom, whose ),which , as, where， when。而which 和as有时可用来表示整个句子。
答案:1. D
