Attributive Clause 定语从句一、排除定语从句的可能：1. 空格后句子完整，不缺乏任何成分时，2. 没有先行词，又不以前句内容为先行词时，3. 前面的先行词为fact，evidence等总括后面具体内容的名词时e.g. Although many people view conflict as bad, conflict is sometimes useful in that it forces people totest the relative merits of their attitudes and behaviors.The mere fact that most people believe nuclear war would be madness does not mean that it will not occur.二、关系副词的选择when where why how关系代词的选择指人who(m), whose, that, which指物which, that, whose ( which/that 指人或物时可省略)指概念as, which 作定语whose, which三、关系代词that 与 which的区别指人时：who: 1 一般情况下，指人即用who或whom2 非限定性定语从句which: 1 指人的品质时2 非限定性定语从句中,先行词表示职业,职务时,尤其在从句中又作补语时3 先行词性别不明时that: 1 关系代词在限定性定语从句中作表语时2 关系代词在定语从句中作there be 的真实主语时3 先行词被形容词最高级only, very , all, any,等修饰时4 先行词包含既指人也指物的并列名词时指物时：which: 1 用于非限定性定语从句2 直接用于介词后3 先行词that, this 时that: 1 先行词被all , any, every, some, (a) few, (a) little, much, no等修饰，或先行词本身就是all, any, little, much, one, anything, everything, nothing等不定代词时2 先行词由序数词或next, last 修饰时3 先行词被形容词最高级修饰时4 先行词被the same, only, very等强调词修饰时四、关系代词前介词的选择1.定语从句中名词、动词、形容词的搭配e.g.They are the national heroes in whose honor a monument was built.2.先行词表方式、工具、程度、速度、目的、时间、材料等时，由先行词决定e.g.Can you see the way in which a computer works.3. 介词＋which/whom前有名词时e.g.We organize a training course, the purpose of which is to help our students pass CET-4.We organize a training course, of which the purpose is to help our students pass CET-4.4.当关系代词引导的非限定性定语从句前有数词,不定代词,最高级等时，中间要用of非限定性定语从句当数词,不定代词,最高级(e.g. one,either,half,several,the largest)等用在关系代词引导的非限定性定语从句前时，中间要用of。

e.g.There were 500 passengers, of whom121 drowned.There were two cigarettes left, one of which was stained with lipstick.There were two extremes in music, both of which can result in risk.The comments made by the volunteer drivers, some (half) of whom were newly qualified, were very revealing.Ex.1. The professor could hardly find sufficient grounds _____ his arguments in favour of the new theory.A. on which to baseB. which to base onC. to base onD. to be based on (006-36-46 9801-42)2. A survey was carried out on the death rate of new-born babies in that region, _____ were surprising. (991-42)A. as resultsB. which resultsC. the results of itD. the results of which3. We need a chairman _____. (986-62)A. for whom everyone has confidenceB. in whom everyone has confidenceC. who everyone has confidence ofD. whom everyone has confidence on4.The course normally attracts 20 students per year, _____ up to half will be from overseas. (986-70)A. in whichB.for whomC. with whichD. of whom5. The residents, ____ had been damaged by the flood, were given help by the Red Cross. 9306-68A. all their homesB. all those homesC. all of whose homesD. all of their homesThe residents, ____ had been damaged by the fire, were given help by the Red Cross. 9306-68A. all of their homesB. all their homesC. whose all homesD. all of whose homes6. Living in the central Australian desert has its problems, _____ obtaining water is not the least. 9806-42A. for whichB.to whichC. of whichD. in whichLiving in the western part of the country has its problem, ____ obtaining fresh water is not the least. 0006-46A. with whichB. for whichC. of whichD. which五、as作为关系代词，引导定语从句1)as 作关系代词,常用于the same …as, such…as 和as…as结构中引导限定性定语从句,代表前面作为先行词的人和物。

e.g. Such books as I have read are classical works.I have never seen such a talented young man as he is.I’d like to use the same tool as is used here.2) as作为关系代词，引导非限定性定语从句关系代词as还可以单独使用，引导非限定性定语从句来说明整个主句，位置较为灵活，可位于句首、句中、句末，一般用逗号与主句隔开。

e.g. As might be expected, John was admitted to the university.She usually takes a rest after lunch, as is her habit.As a poet points out, life is but a dream.3)类似的表达还有as is well known, as is often the case, as you say ,as may be imagined, as often happens, as has been said before, as will be shown in, as is hopedEx.1.The British are not so familiar with different cultures and other ways of doing things, ____is often the case in other countries. 9806A. soB. asC. whatD. that2. He never hesitates to make such criticisms ______ are considered helpful to others. 9201-6A. thatB. asC. whichD. what3. The size of the audience, we had expected, was a thousand.A. WhenB. whoC. asD. that4. , many centuries had passed before man had learned to use fire.A. What is known to allB. Since it has known to allC. As long as it is knownD. As is known to all六、as与which代表主句(部分)概念的区别as引导的定语从句一般对先行词或句子从正面进行辅助说明，常含有“正如”之意。

1．as引导的定语从句常可置于先行词或句子之前或中间，而which引导的定语从句通常跟在先行词之后。