关系代词as与which的用法区别
定语从句中关系代词as与which的用法
学法新探关系代词as与which在定语从句中有时可以相互替换，但又有不同之处，稍不留心，极易使用不当，出现差错。
对此，笔者剖析了关系代词as与which在定语从句中的用法，以期能够帮助同学们准确把握和运用。
一、关系代词as与which在限制性定语从句中的用法关系代词as、which均可以用于限制性定语从句中，有时可以相互替换，但两者仍有着一定的差异，具体体现在：（1）当定语从句中的先行词为某物，且先行词前面有so,such,the same，as many/much等修饰语时，则只能用as引导限制性定语从句，不能用which引导。
比如：①It’s the same book as I bought yesterday.这本书和我昨天买的一样。
（不能用which代替as）②HongKong is so prosperous a city as is referred to as a shop-ping paradise.香港是一个繁荣的城市，被称为购物天堂。
(不能用which代替as)③These housed are sold atsuch a low price as people expected.这些房子按人们预料的那样低价出售了。
(不能用which代替as)（2）当先行词是表示某物的名词或代词时，且在从句中又做介词宾语时，则不可以用as引导限制性定语从句，只能用which引导限制性定语从句。
如：①Thisis the good car on which I spent all my money.这是我花了所有钱买的那辆好车。
（不能用as代替which）③This is the knife with which we cut the bread.这是我们切面包用的刀。
（不能用as代替which）③There is amountain of which the top is always covered with snow.有一座山顶总是覆盖着雪的山。
as which在定语从句中 区别
as和which引导非限制性定语从句的区别1.as引导的非限制性定语从句1)位置灵活，可以置于主句的句首、句中或句末；2)先行词不可是一个词，必须是整个主句或主句的部分内容；3)有“正如、像”等意思，表依据、评论（、态度、看法）等；如：a.This elephant is like a snake，as anybody can see．像任何人都能看见那样，这头象像条蛇。
b.He failed in the exam, as we had expected.c.Tom has passed the test, as everybody knows.正如每个人所了解的那样，汤姆通过了考试。
【比较：Bamboo is hollow，which makes it very light．竹子是空的，这就使得它很轻。
】4)常用以下谓语动词的主、被动语态：know, see, say, expect, imagine, hope, believe,announc e, suggest, report, point out…,例：a.主动（做宾）：as we all know, as you know,as everybody knows;as you see, as wecan see,as we have seen, as anybody can see; as was expected; as we canimagine,as we have imagined…a)As we all know, the earth is round.b)He was a foreigner, as I know from his accent.c)Mike, as we expected, attended the meeting．像我们所期望的那样，迈克参加了会议。
b.被动（做主）：as is known to everybody,as is known to all; as has been expected;as is often the case (with …)，as has been pointed out, as is usual with, as isreported in the newspaper…a)He is an honest man, as is known to all.b)As is often the case with young people, he was overconfident.c)He wasn't unconscious，as could be judged from his eyes．他并未失去知觉，这从他的眼神可以判断出来。
定语从句中关系代词 as, which的区别
关系代词as, which的区别
5.从句内容为否定意义时，常用which： The young lady married an old man with a lot of money， which is disgraceful（不光彩的）. 6.如从句中行为动词是含有复合宾语结构，一般 要用which作主语： Tom has made great progress, which mቤተ መጻሕፍቲ ባይዱde us happy.
定语从句中关系代词 as, which的区别
关系代词as, which的区别
1.放句首或句中引导从句，只能用as; 从句在句末，无其他限制条件时，既可用 which，也可用as。 句型模式为：as …,主语＋ 谓语； 主语， as…， 谓语； 主语＋ 谓语，as/which… 2.当从句和主句语义一致时，用as，反之则用 which: She has married again, as was expected. She has married again, which was unexpected.
关系代词as, which的区别
[备注] (1)the same ...as ...表示相似的东西 the same ...that ...表示同一人或物 This is the same knife as I lost. 这把小刀和我丢的那把一样。 This is the same knife that I lost. 这把小刀就是我丢的那一把。 （2）such ...as 像……那样(定语从句) so/such ...that 如此……以至于…… (结 果状语从句)
关系代词as, which的区别
4.固定搭配：
在引导词＋be ＋done 结构中省略be时，只能 用as： The material resists heat （耐热），as shown in the experiment. 常见固定用法as is well known, as is often the case, as often happens, as has been said before, as has been pointed out, as can be seen等常用as，意为“正如” ： The air show（航空展 ） being held in Zhuhai is fantastic, as can be seen. It never rains but pours in this area, as is often the case.
非限制性定语从句中的关系代词which和as用法辨析
龙源期刊网 非限制性定语从句中的关系代词which和as用法辨析作者：邵玉金来源：《新高考·高三英语》2013年第03期请看下面两道题：① He has won the game， was expected.② He has won the game， was unexpected.A. thatB. whichC. itD. as以上两题选项中均含有关系代词which和as，该选哪一个呢？现就以下几个方面来谈一谈它们的区别（本文所谈的which和as是指引导非限制性定语从句中的关系代词which和as）。
一、位置关系：关系代词which不能放在句首；关系代词as 既可以放在句首也可以放在句末，甚至还可以放在句中。
1. As is known to all， he studies very hard.（不可用which）2. New concept English is intended for foreign students， which is known to all of us.（which不可放在句首，这里也可以用as）3. He， as you know， is clever.二、内涵关系：as有“正如”、“就像”之意，即主从句意义一致；which 则没有此意。
He is a foreigner from North America， as I know from his accent. （as表示“正如”之意）Tom is so busy that he has to work at weekends，which he doesn’t like.三、先后关系：as引导的多为经常性行为，或先于主句发生的动作；which引导的多表示发生在主句之后的行为。
which和as的用法归纳及比较
which 和as 的用法归纳及比较一、which 引导名词从句的用法比较which 作为连接代词，可以引导名词从句，作为连接代词，可以引导名词从句，在从句中作主语、宾语、定语或表语等语法成分。
that 在引导名词从句时，只起连接主句和从句的作用，其本身没有任何含义，不翻译。
例如：译。
例如：（1）Which is better depends on these two clothes’ quality.（2）That Tony can’t swim is unbelievable.（3）I don’t know w I don’t know which I should choosehich I should choose ，because the red andthe yellow are both beautiful.（4）I think that you can do it better.从例句中我们可以看到，which 和that 都可以引导主语从句和宾语从句，但是在（1）句和（3）句中which 在从句中分别作了主语和宾语成分，而在（2）句和（4）句中that 在从句中不作任何成分，只起到连接主句和从句的作用。
从句中不作任何成分，只起到连接主句和从句的作用。
二、which 引导定语从句的用法比较which 作为关系代词，可以引导定语从句，在从句中可以代替物作主语和宾语等语法成分。
例如：分。
例如：（5）This is the book which/that I bought last week.（6）The clothes ，which are over there ，seem to have a goodquality.从（5）句和（6）句中我们可以看到which 可以引导限制性和非限制性定语从句，并分别在句中作宾语和主语成分。
一般情况下，that 和which 在引导定语从句中代替物时可以互用，但以下情况一般要用which ：非限制性定语从句中关系代词一般要用which ； 关系代词前如有介词、关系代词须用which ，如把介词移至动词后，可用that （或省略）；如果先行词是that ，关系代词应用which ；如先行词和定语从句之间被其它较长的成分分隔，常用which ；在“those+复数形式的名词”结构中，其后的关系代词多用which ；一个句子中如有两个定语从句，第一个定语从句用了关系代词that ，第二个从句中的关系代词宜用which 。
定语从句中as与which用法异同 (1)
定语从句中as 与which用法异同摘要：定语从句作为高考必考的语法项目之一，受到同学和教师的关注。
为了使同学们在高三学习及以后的复习阶段有章可循，不盲目，不失分，本文就定语从句中as和which 的用法作一简单比较。
关键词: as 与which 异同定语从句在高中语法的学习中是一个难点，也是高考必考的语法项目之一，为了使同学们在高三学习及以后的复习阶段有的放矢，现将定语从句中as和which的用法做一比较，供大家参考。
一、在限定性定语从句中as 和which 作为关系代词用法有差异：⑴、as 常与such, the same, as, so等词连用构成定语从句。
as 在定语从句中作主语、宾语、表语，这时作宾语的as 不可以省略。
as 在从句中指前面提到的人或物。
Such people as (people such as) you describe are rare nowadays.(你所描述的人现在已很少见了。
)I have the same trouble as you ( have ).(我和你有同样的困难。
)张道真 1995 实用英语语法［M］北京外语教学与研究出版社（7）：573-574He is as great a man as ever lived.注意：①the same ---as 引导的定语从句和the same ---that 引导的定语从句不相同。
the same---as 表示的是“和---一样的”所指的是同一类事物。
the same---that表示的是“如---一样的”所指的是同一个事物。
下面试比较：I bought the same dictionary as you bought.（我买了一本和你的一样的词典。
）I met the same person that I saw yesterday.（我遇见了昨天你看见得那个人。
）马德高，朱崇军 2008 高中英语语法全解［M］北京中国社会出版社 (7):252②such--- as---中，as 引导定语从句，as 在从句中作主语、宾语等; such--- that ---中的that 引导的是结果状语从句。
非限制性定语从句which和as的用法
非限制性定语从句which和as的用法非限制性定语从句which和as的用法我们知道，as和which作为关系代词都可以用来引导非限制性定语从句，指代整个主句所表达的内容，在从句中作主语或宾语，但它们在用法上有区别，这一点许多学生往往搞不清楚。
现就它们引导非限制性定语从句的用法简述如下：一、相同之处当从句位于主句之后，引导词指代整个主句所表达的全部意义时，as和which可以互换。
如：The elephant is like a snake,as/which everybody can see.大家都看得出，这头大象像条蛇。
A big earthquake occurred there last night,as/which was reported on TV.据电视报道，昨夜那里发生了大地震。
She is from Shanghai,as/which I know from her accent.她来自上海，那是我从她的口音知道的。
二、不同之处1、as引导非限制性定语从句时，位置比较灵活，可位于主句之前，也可位于主句之中或之后;而which引导非限制定语从句只能位于主句之后，不能位于主句之前。
如：_______ is known to everybody,the moon travels round the earth.A.ItB.AsC.ThatD.Which答案：B_______ is mentioned above,the number of the students in senior high schools is increasing.A.WhichB.AsC.ThatD.It答案：BAir,as we know,is a gas.众所周知，空气是一种气体。
He is very careful,as his work shows.他的工作表现表明他非常谨慎。
as引导非限制性定语从句常有“如同......那样”的含义，因此在一些固定结构中，如：as we know;as is known to all(众所周知)as we all can see(正如我们大家都能看到的那样)as has been said before/above(正如前面所述)as has been pointed out(正如所指出的那样)as might be imagined(可以得到)as might be expected(正如所预料的那样)as is often the case(情况通常是这样)以上种种固定搭配，一般不能用which代替as。
as引导非限制性定语从句时与which的区别
as引导非限制性定语从句时与which的区别的区别1.当主句和从句语义一致时，用as；反之，用which来引导非限制性定语从句来引导非限制性定语从句 2.当非限制定语从句为否定时，常用which引导。
引导。
3.AS可句子首或尾只在主句后面。
可句子首或尾 which只在主句后面。
4.such，same修饰先行词时关系词用as，介词后用which as/which都可以引导非限制性定语从句。
当引导词在从句中充当主语，若从句谓语动词是非be动词，只能用which.其他情况，比如引导词作主语，谓语动词均可。
是be动词，或者做宾语，或者做补语，as和which均可。
he said he was a king,which surprised me.只能用which he said he was a king,which/as was a lie. he said he was a king,which/as i don't believe. 若果定语从句移到前面则无论什么情况都用as as i believe,......... as is known to all,.......... as we all know,.......... as is reported,................ as is said,...... 2|评论Which as 1、语义的区别、语义的区别当主句和从句语义一致时，用as；He made along speech,as we expected. 当主句和从句语义转折不一致时，用which，He made along speech,which was unexpected. 2、位置的区别、位置的区别不可能放在句首。
看到句首一定用as，which 不可能放在句首。
as we all know, as is mentioned above as often happens as is often the case As is well known 3、含义的区别、含义的区别as有“正如”的含义，which没有此含义。
which与as引导定语从句的区别 之谈
which与as引导定语从句的区别之谈常见的定语从句引导词一般为关系代词：who,whom,whose,which,that 和关系副词：when,why,where. 而作为比较另类的as用作关系代词和关系副词引导的定语从句，有时候就被大家忽略了。
众所周知，which与as都可以引导定语从句，但它们有许多用法上的区别，现就此简要分析如下：一、which与as引导非限制性定语从句的区别：1.Which只能放在主句后面，而as引导的从句位置相对较灵活，可在前，可在中，也可在后。
例如：A）As he realized, I was very useful to him.（在前）B）Air, as we know, is a gas.（在中）C）He was a foreigner, as I know from his accent.（在后）2.在which引导的定语从句中，谓语动词若是am, is, are则这些系动词不能省略；而as 后面若是这种情况，则可以省略。
例如：A）He is a teacher, as （is）clear from his manner.（is可以省略）B）He said he had never seen her before, which was not true.（was不可省略）3.当which引导的从句在意义上近乎并列关系时，可以用and this，and that代替，意思是“这件事”例如：A）He changed his mind, which（and this, and that）made me very angry.他改变了主意，这使我很生气。
B）She has married again, which（=and this, and that）was unexpected.出乎意料的是，她又结婚了。
而as主要起与上下文连接的作用，表达说话人的看法、观点，并指出主句内容的出处或根据等，例如：C）Einstein, as we know, is a famous scientist.爱因斯坦，众所周知，是位伟大的科学家。
as_which引导定语从句的区别
众所周知，which与as都可以引导定语从句，但它们有许多用法上的区别，现就此简要分析如下：一、which与as引导非限制性定语从句的区别：1．Which只能放在主句后面，而as引导的从句位置相对较灵活，可在前，可在中，也可在后。
例如：A) As he realized, I was very useful to him.(在前)B) Air, as we know, is a gas.（在中）C) He was a foreigner,as I know from his accent.(在后)2.在which引导的定语从句中，谓语动词若是am, is, are则这些系动词不能省略；而as后面若是这种情况，则可以省略。
例如：A) He is a teacher, as (is) clear from his manner.(is可以省略)B) He said he had never seen her before, which was not true.(was 不可省略)3.当which引导的从句在意义上近乎并列关系时，可以用and this，and that 代替，意思是“这件事”例如：A) He changed his mind, which(and this, and that)made me very angry.他改变了主意，这使我很生气。
B) She has married again, which(=and this, and that)was unexpected.出乎意料的是，她又结婚了。
而as主要起与上下文连接的作用，表达说话人的看法、观点，并指出主句内容的出处或根据等，例如：C）Einstein, as we know, is a famous scientist.爱因斯坦，众所周知，是位伟大的科学家。
D）As is announced in today’s newspaper, we must improve our style of work.今天的报纸上说，我们必须改进工作作风。
as和which的区别和用法
as和which的区别和⽤法我们知道as 和 which 都可⽤作关系代词来引导从句，它们两个到底有什么不同呢，这是我们经常觉得困惑的地⽅。
下⾯详细讲讲它们之间的联系和区别和各⾃的⽤法。
⼀、as, which 指代整个句⼦或短语。
由as, which 引导的⾮限定性定语从句，相当于and this或and that。
在很多时候，表⽰说话⼈对话语的看法或态度，此时它们的先⾏词并不是具体的某个词，⽽是整个句⼦或短语： The Chinese government has decided to develop the west of China, which, I dare say, will benefit the people there, especially those who are still leading a poor life. 中国政府决定开发西部，我敢说，这将造福于西部的⼈民，特别是那些⾄今过着贫穷⽣活的⼈。
She has married again，which delighted us．她⼜结婚了，这使我们很⾼兴。
John said he’ d been working in the office for an hour，which was true． The result of the experiment was very good， which we hadn’t expected． Carol said the work would be done by October，which personally I doubt very much． ⼆、as, which ⽤在句末的时候，有些情况下可以互换使⽤。
He was late for school，as/which was usual with him．他上学迟到，这是家常便饭。
He was a foreigner，as/which I knew from his accent．他是个外国⼈，我从他的⼝⾳中得知这⼀点。
英语中关系代词which和as的区别
英语中关系代词which和as的区别(1)位置上，as可放在句首、句末，也可插入主句中;which一般放在主句之后(有时也可用as)：As we all know, reading is very important.Reading is very important, which we have already known when we were very young.(2)意义上，as有正如、按照、正像之意，一般用在肯定句中;which 可用于含肯、否定意义的句子中：He failed in the exam again, as was expected.He failed in the exam again, which was unexpected.(3)当定语从句所修饰的主句内容是谓语动词的对象时，常用as，如：Jack was admitted into the university, as we had expected.(4)固定结构，用as：as has been said before as often happensas is well known as we all can seethe same...as such...as(5)当关系代词代表主句引起的结果，又做主谓宾补(SVOC)结构中的主语时，多用which：He passed the exam, which made him delighted.(6)在从句中作介词宾语时，用which，如：They went to the zoo, after which they saw a film. (7)在从句中代表主句中的谓语的整个概念时，常用which，如：He can write a letter in English, which I cannot.(8)指代主句中某一名词时，多用which，如：Beijing, which he was born, is our capital.(9)代替主句中的形容词时, 常用which，如：Lily thought me clever, which she herself was.在定语从句中，相比于which VS that，who VS that，我们对which 与as两者区别的关注度要少很多，在遣词造句或是口语表达中，也常常是“跟着感觉走”。
as与which引导非限制性定语从句的区别
as与which引导非限制性定语从句的区别作者：董军权来源：《广东教育·高中》2013年第11期在教学实践中，尤其在批改作文中笔者发现，有的学生对as与which引导非限制性定语从句的用法模棱两可，含混不清。
下面从两者的用法区别展开说明，以便正确地使用。
1. 从指代的异同来说，as指代整个句子；which指代整个句子或者主句中的某个成分。
如：She is not unconscious，as can be judged from her eyes.她并未失去知觉，这从她的眼睛里可以看出。
（as指代整个句子）Mother always asked him to study hard，which helped him a lot. 他妈妈总是让他刻苦学习，这一点对他帮助很大。
（which指代整个句子）The house， which was built fifty years ago， stood still in the earthquake. 这所建造于50多年前的房子，在地震中依然耸立着。
（which指代具体的先行词）2. 就主句与从句的位置关系来说，as引导的从句可放在主句的前面或者主句的后面；which引导的从句只能放在主句的后面。
如：As everybody knows， knowledge is power. 众所周知，知识就是力量。
Knowledge is power， as everybody knows.众所周知，知识就是力量。
Knowledge is power， which is accepted widely all over the world.知识就是力量，这一点世界公认。
3. 从意义上来说，as意为“正如，像，由……而知”； which意为“这就使得，这一点”。
如：He is a great hero， as is described in the report.正如在报道中描述的一样，他是一个伟大的英雄。
as 和which的区别
which与as引导非限制性定语从句的异同which与as一样，都可以引导非限制性定语从句，它们既有相同之处，也有差别。
因此在实际运用中容易混淆。
它们的某些用法在高考中也会考查。
一．相同点。
两者引导非限制性定语从句时，可指代主句中的部分或整个句子的内容，在从句中做主语，宾语或表语，位于主句之后有时可互换。
The meeting was put off, as /which was exactly what we wanted.He was a doctor, as/which I knew from his manner.二．不同点1. as可指其前后主句提到的事实或情况，因此引导的非限制性从句位置比较灵活，which可以放在主句前后，也可插入主句之中；而which引导的非限制性从句只能位于主句之后。
As is known to all, fish can’t live without water.Air, as we know, is gas.2.在非限制性从句中，which后的be动词不可省；as而后的be动词可以省略。
She told me she won the match , which was a lie.The material is elastic, as (was) shown in the figure.3. which在非限制性定语从句做主语时可用各类动词做谓语；而在非限制性定语从句做主语时，谓语常用连系动词，如be, seem, become等，一般不用其他行为动词。
He saw the girl, which delighted him.He didn’t say anything at the meeting , as/which seemed very strange.4. 如果主句中叙述的事情与从句所涉及的意向一致，多用as，用以对主句的意义进行补充；如果不一致，就用whichShe has married again, as was expected.He broke the rules again, which was unexpected.5.如表示“如同。
关系代词as与which的用法区别
关系代词as与which的用法区别as 和which的相同点(1) as 和which都可引导非限制性定语从句，放在主句之后；在非限制性定语从句中充当从句的主语、宾语或表语。
如：Tom has found a good job, as / which we all hope. 汤姆找到了一件好工作，■as 和which的相同点(1) as 和which都可引导非限制性定语从句，放在主句之后；在非限制性定语从句中充当从句的主语、宾语或表语。
如：Tom has found a good job, as / which we all hope. 汤姆找到了一件好工作，这正是我们大家所希望的。
(2) as 和which都可代表整个句子的内容或主句中的某一成分。
如：His mother is ill, which makes him very sad. 他母亲病了，这件事情使他很难过。
He has made great progress, as / which makes us very happy. 他进步了，这使得我们很高兴。
以上两句中的as / which都指前面整个句子的内容。
Though he has lots of money, he still rides his old bike, which was bought ten years ago. 尽管他很有钱，但是他还骑着他的旧单车，这单车是十年前买的。
There you can meet many writers as you have ever read in books. 在那里，你可见到你在书中所读过的很多作家。
■as与which的区别(1) 当先行词前面有so + adj. + a / such + (a) + adj. , the same等词修饰时，引导词只能用as，而不用which。
如：She is so nice a girl as we all like. 她是个我们大家都喜欢的如此好的女孩。
as_which引导定语从句的区别
众所周知，which与as都可以引导定语从句，但它们有许多用法上的区别，现就此简要分析如下：一、which与as引导非限制性定语从句的区别：1．Which只能放在主句后面，而as引导的从句位置相对较灵活，可在前，可在中，也可在后。
例如：A) As he realized, I was very useful to him.(在前)B) Air, as we know, is a gas.（在中）C) He was a foreigner,as I know from his accent.(在后)2.在which引导的定语从句中，谓语动词若是am, is, are则这些系动词不能省略；而as后面若是这种情况，则可以省略。
例如：A) He is a teacher, as (is) clear from his manner.(is可以省略)B) He said he had never seen her before, which was not true.(was 不可省略)3.当which引导的从句在意义上近乎并列关系时，可以用and this，and that 代替，意思是“这件事”例如：A) He changed his mind, which(and this, and that)made me very angry.他改变了主意，这使我很生气。
B) She has married again, which(=and this, and that)was unexpected.出乎意料的是，她又结婚了。
而as主要起与上下文连接的作用，表达说话人的看法、观点，并指出主句内容的出处或根据等，例如：C）Einstein, as we know, is a famous scientist.爱因斯坦，众所周知，是位伟大的科学家。
D）As is announced in today’s newspaper, we must improve our style of work.今天的报纸上说，我们必须改进工作作风。
as which 的区别
1、as与which的用法区别：(1)引导限制性定语从句时，在such,as,thesame后只能用as，其他情况用which：如：I never heard such stories as he tells. 我从未听过他讲那样的故事。
It's the same story as I heard yesterday. 这故事跟我昨天听到的一样。
This is the photo which shows my house. 这张照片拍的是我的住宅。
(2)引导非限制性定语从句时，有时两者可互换：如：I live a long way from work, as [which] you know. 我住得离工作单位很远，这你是知道的。
(3)但在，在以下情况引导非限制性定语从句时，两者不可换用：①当从句位于主句前面时，只用as：如：As is known to everybody, the moon travels round the earth once every month. 月球每月绕地球转一周，这是每个人都清楚的。
②as引导的非限制性定语从句应与主句在意义上和谐一致，which无此限制：如：He went abroad, as[which] was expected. 他出国了，这是大家预料到的。
He went abroad, which was unexpected. 他出国了，这让大家感到很意外。
(不用as)③as引导非限制性定语从句时，先行词通常不能是主句中某个具体的词，而应是整个句子、整个短语或某个短语推断出来的概念，而which则无此限制：如：The river, which flows through London, is called the Thames. 这条流经伦敦的河叫泰晤士河。
(不用as)④当as引导非限制性定语从句作主语时，其谓语通常应是连系动词，而不宜是其他动词，而which则无此限制：如：She has married again, as[which] seemed natural. 她又结婚了，这似乎很自常。
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关系代词as与which的用法区别
■as 和which的相同点
(1)as 和which都可引导非限制性定语从句，放在主句之后；在非限制性定语从句中充当从句的主语、宾语或表语。
如：
Tom has found a good job, as / which we all hope. 汤姆找到了一件好工作，这正是我们大家所希望的。
(2)as 和which都可代表整个句子的内容或主句中的某一成分。
如：
His mother is ill, which makes him very sad. 他母亲病了，这件事情使他很难过。
He has made great progress, as / which makes us very happy. 他进步了，这使得我们很高兴。
以上两句中的as / which都指前面整个句子的内容。
Though he has lots of money, he still rides his old bike, which was bought ten years ago. 尽管他很有钱，但是他还骑着他的旧单车，这单车是十年前买的。
There you can meet many writers as you have ever read in books. 在那里，你可见到你在书中所读过的很多作家。
■as与which的区别
(1)当先行词前面有so + adj. + a / such + (a) + adj. , the same等词修饰时，引导词只能用as，而不用which。
如：
She is so nice a girl as we all like. 她是个我们大家都喜欢的如此好的女孩。
It is such an interesting book as we all want to read. 它是本我们大家都想读的有趣的书。
上面两句中的as就不能用which替换。
(2)as 在从句中常作宾语；作主语时，从句的谓语动词常为系动词，即：系表结构或被动结构。
如：
As you expected, he turned up on time. 正如你所愿，他按时到了。
As is said above, he has conquered the difficulty. 正如上面所说，他征服了困难。
(3)当非限制性定语从句放到主句的前面时，引导词只能用as，而不用which。
如：
As is planned, we got there before eight. 正如计划，我们再把店前到达了那儿。
(4)As引导的非限制性定语从句指表示积极的意义，与主句是顺理成章的关系，绝不能与之矛盾。
若非限制性定语从句表示一种消极的意义，则只用which。
如：He has succeeded in his career, as / which we all hope. 他在事业中成功了，这正是我们大家所希望的。
Her grandma died last week, which made her very sad. 她的奶奶逝世了，这使得她很悲伤。
(5)当非限制性定语从句的引导词前面有介词时，只能用which, 而不可用as。
如：
He has a new computer, for which he paid nearly ten thousand yuan. 他有一台新电脑，这台电脑花了他将近一万元。
(6) 当关系代词代替主句中的宾语从句或复合结构(如：宾+补；不定式短语；动词-ing 形式短语等) 时，一般只能用which, 而不用as。
如：
She told us that there was something wrong with her bike, which was true。
她告诉我们说她的单车出了毛病，这话是真的。
He asked her to help him with his English, which she did. 他请她教他学英语，她的确帮了。
(7) 关系代词仅代表主句中的谓语部分时，从句中谓语部分被省略而只保留情态动词的否定式或助动词否定式，引导词一般只用which, 而不用as。
如：
He speaks English very fluently, which I can’t. 他的英语说得非常流利，这我可不行。
(8)关系代词作定语修饰后面的名词时，一般只用which, 而不用as。
如：
He suggested going swimming in the river, which idea we agreed with. 他提议去河
里游泳，我们就同意了他的想法。
(9)当关系代词仅代表主句中单个的名词时，一般只用which, 而不用as。
如：
He sent me a beautiful present, which I valued very much. 他给寄来了一件精美的礼物，我对它非常珍视。
(10)as 在非限制性定语从句中，还常跟such连用。
如：
There was a look of love in the teacher’s eyes, such as mothers have for their childr en. 老师眼里流露出对他喜爱的神情，就好像母亲对孩子的喜爱。
(11)as常用于一些固定结构中。
如：
as is well known / as we all know 众所周知；a s is said above 正如上面所说；
as might be imagined 正像所想象的那样；as is reported 如报道所说；
as has been pointed 如所指出的那样；as is expected 正如所料。