关于介词+which的用法和意思？
介词+which中，有结构in,on,by,during,for,at等用法
一般情况下on; in; by+which在表示时间时使用
on; in; at+which则表示地点状语
for+which表示原因
求教介词+which的用法
关于“介词 + which / whom”引导的定语从句
“介词+关系代词”引导的定语从句，是定语从句一种介词前置的定语从句句型，介词与关系代词之间存在一种介宾关系。当关系代词在定语从句中作介词宾语时，把介词置于关系代词前，即演变出“介词+关系代词”句型。例如：
The man who/whom /that you spoke to is a teacher.
=The man to whom you spoke is a teacher.
一、基本构成
1.“介词+关系代词”结构引导的定语从句中，关系代词只能用which（指物）或whom(指人) ，即：介词+which/whom。
（1）The man to whom you spoke is a teacher.
（2）The city in which she lives is far away.
（3）The little girl is reading a book, in which there are many cartoons.
注意：当介词放在关系代词的前面时，用在介词后的关系代词不能省略。
2.在限制性定语从句中，当介词置于定语从句的谓语动词之后时，可用that/which(指物)；that/who/whom（指人）作介词的宾语.且此处关系代词可以省略，特别是在口语中。如：
（1) The man (who/whom /that )you spoke to is a teacher.
（2）The city（which/that）she lives in is far away.
注：通常介词放在定语从句中动词后，也可以放在关系代词前面，但有些特殊动词短语搭配不能拆分，介词只能放在动词后，如： look for, look after, pay attention to ,take care of , look forward to, listen to等。
This is the pen that / which you are looking for.
The patient whom she is looking after is her father.
The words that /which we should pay attention to are written on the blackboard.
There are fifty patients who/whom/that we must take good care of.
二、关系副词when，where，why可用“介词＋which”来代替。关系副词实际上是介词＋先行词。其中
when=表时间的介词（如：in，at,during等）+which；
Where=表地点的介词（如：in，at,on,under等）+which；
Why=表原因的介词（如：for）+which
(1)当先行词表示时间，定语从句中缺少时间状语时，通常用关系副词when引导，此时也可选用表示时间的介词＋which来代替关系副词when。
I still remember the day when I came here. ( on the day =when)
(2)当先行词表示地点，定语从句中缺少地点状语时，通常用关系副词where引导，此时也可选用表示地点的介词＋which来代替关系副词where。
This is the house where I lived last year. ( in the house= where)
(3)当先行词为reason，定语从句中缺少表示原因状语时，通常用关系副词why引导，此时也可以用for which来代替关系副词why。
There are many reasons why people like traveling. (for the reasons =why)
三、关系代词前介词选择三原则：一先，二动，三意义（重中之重）
1.一先，即根据定语从句中介词与先行词的搭配关系选择。
I never fet the day on which I came to this school. (on the day)
2.二动，即根据定语从句中谓语动词与介词的搭配关系选择。
This is the iPad on which I spent 3000 yuan. (spend money on sth.)
3.三意义，即根据定语从句的意义来确定介词。
This is my pair of glasses, __without which__I cannot see clearly.
例题：用“介词+关系代词”的形式表示
1. Do you like the book __________ she learned a lot?
2. He paid the boy $10 for washing ten windows, most ______ hadn't been cleaned for at least a year.
3. The tower _________ people can have a good view is on the hill.
注意：
介词+关系代词
1）介词后面的关系代词不能省略。
2）that前不能有介词。
3）某些在从句中充当时间，地点或原因状语的"介词+关系词"结构可以同关系副词when,where和why互换。
定语从句中‘介词+which’的用法
介词+WHICH在定语从句中可以代替when,where,和why，用哪一个介词要看先行词和从句谓语动词，介词要能够与先行词搭配使用
、"介词+关系代词"引导的定语从句
关系代词whom, which在定语从句中作介词的宾语时,可以跟介词一起放在主句和从句之间;当先行词指人时,介词后的关系代词用whom, 其余用which,这时的关系代词不能省略;有时为了使关系代词紧跟它所修饰的先行词,也可以把介词放在从句中有关动词的后面,这时的which可用that替换。当介词放在从句有关动词的后面时,关系代词which, that, whom在口语中和非正式文体中经常省略。如:
This is the room in which he used to live. = This is the room (which / that) he used to live in. 这是他过去居住过的房间。
Who's the man with whom you just shook hands? =Who's the man (that / whom) you just shook hands with? 刚才你与他握手的那个人是谁?
但含有介词的短语动词一般不拆开,介词仍放在动词的后面。如:
This is the book (which / that) I'm looking for. 这就是我在找的那本书。
在这类定语从句中,介词的选择一般根据动词的需要,如上述几例,或者根据先行词来决定。如:
There is a mountain of which the top is always covered with snow. 有一座山顶总是覆盖着雪的山。
介词+whom，介词+which的用法
who可以带人（即他的先行词必须是人），在从句中可以做主语，往往也可以代替在从句中代替宾格的whom，但他的前边不能有介词 如果用带介词必须用whom(如果表示某人的 则用whose） 即prep+whom举个例子： She is the girl whom I went there 她就是和我一起去那的女孩 This the hero of whom we are proud 这就是我们引以为荣的英雄注：有些有v+prep组成的短语 关系非常紧密 prep不能前置 介词 in, on, at, for 等与关系代词 which 一起引导定语从句时，可与相关的关系副词 when, where, why 等替换 如why = for+which, when = on / at / in / ... + which,where = at / on / in / ... + which 又如：The reason for which he refused to go to the party was that they had not invited him to. 他拒绝去赴宴的原因是他没受到他们的邀请 America is the country in which Gee Washington was born. 美国是乔治·华盛顿出生的国家