where。
当先行词是case，condition，situation，position，point，stage等名词时，表示情况、方面、处境时，用where引导定语从句。
例如：I can think of many cases where students know a lot of words but don’t write a good essay.
定语从句的先行词是many cases，定语从句的句子结构很完整，故从句中使用关系副词。句意：我能想起很多情况，在这些情况下，学生知道很多词汇和短语，但是却写不出好的文章。
where的用法
1、where可以用作副词
where用作副词的基本意思是“什么地方，哪里”，可用作疑问副词，引导特殊疑问句。
where也可用作关系副词，意思是“在〔往〕哪里”；引导限制性和非限制性定语从句，用于表示地点的词语之后。
where用作从属连词，可引导地点状语从句，相当于in〔at，to〕the place，其前常有加强语气的词，如just，only，even，right等或否定词not，有时某些成分可以省略。
2、where可以用作连词
where用作从属连词，可引导地点状语从句，相当于in〔at，to〕the place，其前常有加强语气的词，如just，only，even，right等或否定词not，有时某些成分可以省略。
where也可引导对比状语从句，相当于while，可译为“而，却，反之”。
where还可引导让步状语从句，语气较轻，从句中常用倒装形式。
case, condition, situation, position, point, stage
等名词后接where引出的定语从句小议
不久前，下面这道题引发了我们对stage作先行词之后的定语从句引导词的问题以及其它类似定于从句的探讨，
先看一道题:
the conflict had developed into a stage ______ the two countries were gathering big troops on the border.
（2009学年第二学期浙东北（zdb）三校期中联考高二英语试卷（2010.05）） a. where b. when c. which d. that
本题到底是选a还是选b？关键问题在于对先行词stage的理解，根据《牛津高阶英汉双解词典》（第七版）简作（oald）的解析：stage: a period of state that sb./sth. passes through while developing or making progress. 既可以理解为事件“(进展或进展的)阶段， 状态”; 又可以理解为“时期”。而上题中作“阶段”或“时期”都理解的通。 再看stage的用法;
*stage名词 n. [c]
1.舞台
some girls are dancing on the stage. 一些女孩在舞台上跳舞。
2.注意中心,活动舞台,场所
3.(进展的)阶段;时期
a caterpillar must pass through the cocoon stage to become a butterfly.
表示这些意思时，当stage作先行词后有定语从句时，。
例句：1.表地点: the stage where the girls are going to dance is in the gym.
2.表时期: the stage when he is preparing for his study is really important.
不同的叙述：
①当先行词为case，condition，situation，position，point，stage等名词，表示情况、方面、处境时用关系副词where.
②当先行词是case, condition, situation, position, point, stage 等名词时，表示情况、方面、处境时，用关系副词where.但先行词是occasion时，用关系副词when.
③当 situation, condition, stage, point，scenes 做先行词时，用 where 引导定语从句
④先行词通常是 time, day, season, age, occasion 等时间名词时其后的定语从句用when引导.
事实上, 当先行词 occasion, point, stage等名词是表示时间节点的时候，其后的定语从句就用when引导，在从句中作时间状语. 例如：
1. i can remember very few occasions when he had to cancel because of ill health.（oald）
我记得他因健康不佳而被迫取消的情况绝无仅有。when引导定语从句，在从句中作时间状语.
2.（2008·山东·26） occasions are quite rare ___________i have the time to spend a day with my kids.
a. who b. which c. why d. when
答案选d。考查定语从句。此题关键是要根据句意判定是定语从句。句意为：我有时间和孩子们一起度过一天的机会很少。occasions 是先行词, 所选关系词在定语从句中要作时间状语, 故选d项
3. we had reached the point when there was no money. 我们那时已到了没有一分钱的时刻。point表示“某一阶段,关头”， 所以其后用when 引导定语从句。
4. there comes a point in your life when you realize: who matters, who never did, who won't anymore
5. china is now at a stage of accelerated industrialization and urbanization when the contradiction between economic growth and environmental protection is particularly prominent.
中国目前正处于工业化和城市化加速发展的阶段,此时经济增长和环境保护之间的矛盾十分突出。source: hard times call for green economy/by hu shaowei (china daily 03/24/2010 page8)
但更多情况是：position，situation, stage, case等，作先行词时，其后的定语从句应用where引导定语从句。如：
1.oxford dictionary online
more examples introducing a clause with 'when ' can be found but it is hard to find an example with 'where' after 'occasion'.
2.it is the same with longman dictionary
"under these conditions, where we see so much uncertainty with leadership succession, possible instability, we see no arms control, we see no confidence building measures, we see no disarmament, we see north korea refusing to return to the six-party talks, we see the sinking of the cheonan and potential clashes in the west sea around the
northern limit line. so a lot of people are just saying this is just not the right time," pinkston said. voa news.
it is the same with ' situation'.
"it moves from a situation where only those items on the permitted list can come into gaza to a situation where things come into gaza as a matter of course unless they are on the prohibited list. it allows us to facilitate the united nations projects for reconstruction in things like schools and hospital and water sanitation and so on." bbc news新闻 20100621
3.we were put in a position in which(=where) we had either to accept we were less important, or fight the government.(人教版新课标高中英语必修1 line25.p34) 我们被置于这样一种境地，或者是被迫承认我们低人一等，或者是与政府作斗争。 这是一个主从复合句，in which引导定语从句，修饰先行词position。
4. can you think of a situation where you once felt embarrassed?
你能设想起你曾经有过感到很窘迫的场合吗?
5.he is the boss of the restaurant where （= in which） we often have lunch.
6. the last thirty years have seen the greatest number of laws stopping our rights and progress until today we have reached a stage where we have almost no rights at all.
(人教版新课标高中英语必修1 line19-20 p34)
注意： 近年来高考对关系副词where的考查趋于复杂化，从先行词为明显的“地点”发展为“模糊的地点化”。事实上，当先行词表示某事物发展的某个situation“情景”、stage“阶段”或某种程度时都可以用where引导定语从句。所以文章开头那道题答案为a. 更多的列子如：
1.（2009·福建·24） it’s helpful to put children in a situation ________they can see themselves differently.
a. that b. when c. which d. where
2.（2009·浙江14）i have reached a point in my life _______i am supposed to make decisions of my own.
a. which b. where c. how d. why
3. an iraqi reporter during a news conference ________threw his shoes at bush and called him a dog in arabic shocked the world.
a. who b. where c. whom d. which
1.【解析】选d。考查定语从句。句意为：把孩子放在一个能使他们从另外一个角度认识自己的环境中对他们有益。当先行词是case, condition, situation, position, point, stage等名词表示“情况, 方面, 处境”时, 关系副词用where。
2. 【解析】选b。考查定语从句。句意为：我已经到了应该自己作决定的那个人生阶段。先行词point和定语从句被介词短语in my life隔开。当先行词是case, condition, situation, position, point, stage等名词表示“情况、方面、处境”时, 定语从句用关系副词where引导。how不能用来引导定语从句; which在定语从句中作主语或宾语; why引导定语从句时先行词应为reason; 因此可排除选项a、c和d。
3. 【解析】选d。考查定语从句。此题关键是要根据句意判定是定语从句。句意为：我有时间和孩子们一起度过一天的机会很少。occasions 是先行词, 所选关系词在定语从句中要作时间状语, 故选d项。
类似的还有如：
4.those successful deaf dancers think that dancing is an activity ____sight matters more than hearing.
a. when b. whose c. which d. where本回答被提问者采纳
where
定 语 从 句
一、基本概念：
在复合句中，修饰某一名词或代词的从句叫定语从句。
定语从句所修饰的词叫先行词；定语从句一般用关系代词或关系副词来引导，关系词放在先行词与定语从句之间起连接作用，同时又作从句中的一个成分。
引导定语从句的关系代词有：that, who, whom, whose, which;
关系副词有：when, where, why.
二、关系词的用法：
（一）关系代词的用法：
1． 作主语用who, which和that。
2． 作宾语用whom, who, which, that。
3． 作定语用whose,。
4． 作表语只用that ，它既可以指人，也可以指物，但时常省略。
（二）关系副词的用法：
1．when 指时间，在从句中作时间状语，它的先行词通常有：time, day, morning, night, week, year 等。
2．where指地点，在从句中作地点状语。它的先行词通常有：place, spot, street, house, room,
city。
3． why指原因或理由，它的先行词只有reason。
例句:
(1)The prosperity which/that had never appeared before took on in the countryside.
农村出现了前所未有的繁荣。(which/that在从句中作主语)
（2）By the time when you arrived in London, we had stayed there for two weeks.
当你到达伦敦的时候，我们在那里已经待了两个星期。
（3）She didn't tell me the reason why she refused the offer.
她没跟我讲她拒绝这项工作的原因。
（4）Gone are the days when they could do what they liked.
他们为所欲为的日子一去不复返了。
（5）Barbary was working in Aubury, where she went daily in a bus.
巴巴拉在奥伯里工作，每天得坐公共汽车去上班。
(6)Is he the man who/that wants to see you?
他是那个想见你的男人吗?(who/that在从句中作主语)
（7）Each time when he goes to business trip, he brings a lot of living necessities, such as towels, soap, toothbrush etc.
他每次出差都带着生活必需品，如毛巾，肥皂，牙刷等其他东西
类型:
限定性定语从句
意义:
限定性定语从句对被修饰的先行词有限定制约作用，使该词的含义更具体，更明确。限制性定语从句不能被省略，否则句意就不完整，例如I met some one who said he knows you.
非限定性定语从句
意义:
非限定性定语从句起补充说明作用，缺少也不会影响全句的理解。在非限制性定语从句的前面往往有逗号隔开，如The house,which I bought has a lovely garden.
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