详细点！
1、根据which引导的从句而定，当从句中需要以in作介词时使用。
例句：The school which he once studied in is veryfamous.
= The school in which he once studied is very famous.
他曾经就读的这所学校很有名。
2、固定搭配
例句：The plane may be several hours late, in which case there's no point in our waiting.
（固定搭配：in the case)
飞机可能会晚点几小时，这种情况下等待是没有意义的。
扩展资料
which是定语从句的关系代词之一，有且仅有两种用法。
1、which前面有逗号，逗号前面是个名词，which就近指代那个名词。
例句：Tankfield emailed Pea some photos, which did not cheer Pea up.
坦克福尔德给皮尔邮件了一些照片，却并没有让皮尔高兴起来。
2、which前面是介词，介词前面是名词，which就近指代介词前的那个名词，名词和介词之间有无逗号均可。
例句：Tankfield once lent Pea a book from which Pea glimpsed the basics of genes.
坦克福尔德曾经借给皮尔一本他曾经在上面瞄到过基因理论的书。
温馨提示：答案为网友推荐，仅供参考
第1个回答 2010-06-14
which 用于定语从句，作关系代词，在句中要做成分
in which 用于定语从句，作关系副词，在句中不做成分，in which=where
in which 只能用在定语从句中，等于where,在定语从句中作状语。
如：He lived in the house in which Tom once lived.
He lived in the house where Tom once lived.
定语从句中.如
this is the room in which we stayed
先行词是room，后的句子是用来修饰room的
但是room不可做stay的成分，因为stay是不及物动词，后不可直接家宾语
所以要有个介词．
其实上述的句子＝
this is the room which we stayed in．
这里的介词是可以提到which 前的本回答被网友采纳
in which 用于定语从句，作关系副词，在句中不做成分，in which=where
in which 只能用在定语从句中，等于where,在定语从句中作状语。
如：He lived in the house in which Tom once lived.
He lived in the house where Tom once lived.
定语从句中.如
this is the room in which we stayed
先行词是room，后的句子是用来修饰room的
但是room不可做stay的成分，因为stay是不及物动词，后不可直接家宾语
所以要有个介词．
其实上述的句子＝
this is the room which we stayed in．
这里的介词是可以提到which 前的本回答被网友采纳
第2个回答 2019-12-07
地点，则不用which。
f;which
you
lost
yesterday(that/，how，作主语）
二。
who
is
the
man
that
is
reading
new
paper
over
there。
先行词;which
can
fly（that/which指物，做主语）
he
is
the
most
careful
boy
that
i
know（that指人，作宾语）
the
man
that
works
in
this
room
is
a
chemist（that
指人：
this
is
the
only
thing
（that）
we
can
do
now.
he
gave
me
the
same
pen
(that)
were
written
by
lu
xun。
这里主要讲解一下再定语从句中的用法、that、which在从句中作主语时，不能省略.
d：定语从句的引导词前面的被定语从句所修饰的名词、代词：
一。
i
may
leave
here
any
time
i
want
to：
is
there
anything
（that）
i
can
do
for
you
town？
that
is
all
（that）
i
know。
b、先行词被序数词所修饰时：
the
first
thing
（that）
we
should
do
is
to
work
out
a
plan、that
可指人，which则不能，指物时：引导词和先行词
引导词：就是引导从句的词：
that
was
the
way
she
looked
after
us。
在下列情况下、
在“the
time
when”等结构和某些事件状语中，when常被that代替，why，关系代词that和which指物时;which
is
grown
in
the
north
of
china.
四、在定语从句中：
1，从句的谓语动词的人称和数须贺先行词一致、当先行词中即有人又有物时：
the
man
and
the
car
（that）you
want
to
see
are
all
here
.你想见的人和车斗在这、关系代词that和which在定语从句中作主语和宾语，放在先行词和定语从句之间，一般没有区别，但下列几种情况中不能互换、anything、little等不定代词（something后也可以用which），what
，起联系作用，一般情况下可互换，如：
here
is
the
pen
that/.在定语从句中充当一定的成分;which
指物作宾语)
a
plane
is
machine
that/，都不能用that，指物时，只能用which和其他关系代词，如：
all
the
books
there，which
have
beautiful
pictures
in
them，were
written
by
him。
这个地方注意一下。
wheat
is
a
plant
that/、先行词被形容词最高级修饰时：
this
is
the
question
that
we
are
had
so
much
discussion
about。
b、在非限定性定语从句，无论指物指人，而且that往往被省略?
this
is
the
very
books
that
were
e。作宾语时在口语中和非正式问题中经常省略、放在介词后面做介词定语时：
this
is
the
question
about
which
we’ve
had
so
much
discussion
但是，如果把介词放在从句后部。这时which
就可换为that并常省略。如上例1和3中的that、which都可省略。
三、关系代词在主语从句中作主语时，when等具有引导其后从句功能呢过得词，只能用which
a，如上例可以改为、只能用that的情况：
a、先行词为all、everything、nothing。
c？
g、先行词被形容词最高级所修饰时：
this
is
one
of
the
most
exciting
football
games（that）i
have
ever
seen.
the
nanjing
yangtse
river
bridge
is
the
longest
bridge
(that)
they
ever
seen。
during
the
time
i
was
there
i
visited
him
twice。
h、
way
后面可根由that引导的定语从句，但that一般都省略，比如whetherwhich的用法
1、在后置的非限制性定语从句中代替上文出现的事物或者情况（单数或复数）。
2、在问句中作疑问代词，在名词从句中作为连接代词用，其含义为“哪儿，哪些”。
3、如果非限制性定语从句的先行词不是指主句内容，而是指具体的人、时间
f;which
you
lost
yesterday(that/，how，作主语）
二。
who
is
the
man
that
is
reading
new
paper
over
there。
先行词;which
can
fly（that/which指物，做主语）
he
is
the
most
careful
boy
that
i
know（that指人，作宾语）
the
man
that
works
in
this
room
is
a
chemist（that
指人：
this
is
the
only
thing
（that）
we
can
do
now.
he
gave
me
the
same
pen
(that)
were
written
by
lu
xun。
这里主要讲解一下再定语从句中的用法、that、which在从句中作主语时，不能省略.
d：定语从句的引导词前面的被定语从句所修饰的名词、代词：
一。
i
may
leave
here
any
time
i
want
to：
is
there
anything
（that）
i
can
do
for
you
town？
that
is
all
（that）
i
know。
b、先行词被序数词所修饰时：
the
first
thing
（that）
we
should
do
is
to
work
out
a
plan、that
可指人，which则不能，指物时：引导词和先行词
引导词：就是引导从句的词：
that
was
the
way
she
looked
after
us。
在下列情况下、
在“the
time
when”等结构和某些事件状语中，when常被that代替，why，关系代词that和which指物时;which
is
grown
in
the
north
of
china.
四、在定语从句中：
1，从句的谓语动词的人称和数须贺先行词一致、当先行词中即有人又有物时：
the
man
and
the
car
（that）you
want
to
see
are
all
here
.你想见的人和车斗在这、关系代词that和which在定语从句中作主语和宾语，放在先行词和定语从句之间，一般没有区别，但下列几种情况中不能互换、anything、little等不定代词（something后也可以用which），what
，起联系作用，一般情况下可互换，如：
here
is
the
pen
that/.在定语从句中充当一定的成分;which
指物作宾语)
a
plane
is
machine
that/，都不能用that，指物时，只能用which和其他关系代词，如：
all
the
books
there，which
have
beautiful
pictures
in
them，were
written
by
him。
这个地方注意一下。
wheat
is
a
plant
that/、先行词被形容词最高级修饰时：
this
is
the
question
that
we
are
had
so
much
discussion
about。
b、在非限定性定语从句，无论指物指人，而且that往往被省略?
this
is
the
very
books
that
were
e。作宾语时在口语中和非正式问题中经常省略、放在介词后面做介词定语时：
this
is
the
question
about
which
we’ve
had
so
much
discussion
但是，如果把介词放在从句后部。这时which
就可换为that并常省略。如上例1和3中的that、which都可省略。
三、关系代词在主语从句中作主语时，when等具有引导其后从句功能呢过得词，只能用which
a，如上例可以改为、只能用that的情况：
a、先行词为all、everything、nothing。
c？
g、先行词被形容词最高级所修饰时：
this
is
one
of
the
most
exciting
football
games（that）i
have
ever
seen.
the
nanjing
yangtse
river
bridge
is
the
longest
bridge
(that)
they
ever
seen。
during
the
time
i
was
there
i
visited
him
twice。
h、
way
后面可根由that引导的定语从句，但that一般都省略，比如whetherwhich的用法
1、在后置的非限制性定语从句中代替上文出现的事物或者情况（单数或复数）。
2、在问句中作疑问代词，在名词从句中作为连接代词用，其含义为“哪儿，哪些”。
3、如果非限制性定语从句的先行词不是指主句内容，而是指具体的人、时间
第3个回答 2010-06-13
千万不要误解！
in which不是一个固定搭配
which只是定语从句中的关系词
至于前面的介词只跟句中的介词短语有关系
举个例子：
he opened the box， in which Mom put some chocolate。
其实隐含的是put sth in some place 这个介词短语
清楚没？
in which不是一个固定搭配
which只是定语从句中的关系词
至于前面的介词只跟句中的介词短语有关系
举个例子：
he opened the box， in which Mom put some chocolate。
其实隐含的是put sth in some place 这个介词短语
清楚没？
第4个回答 2019-05-07
记住哦，in等介词提前，后面一定用which
These
are
the
days
in
—which—
it
takes
two
salaries
for
each
home,but
divorces
increase.
in
which
不是就=where,只有先行词为地点（包括抽象地点）时才相等。此处先行词为
the
days，为时间
These
are
the
days
in
—which—
it
takes
two
salaries
for
each
home,but
divorces
increase.
in
which
不是就=where,只有先行词为地点（包括抽象地点）时才相等。此处先行词为
the
days，为时间
