when 在定语从句中有哪些用法啊?

when 在定语从句中有哪些用法啊?
when 在定语从句中有哪些用法啊?

when 在定语从句中有哪些用法啊?
when
[(h)wen]
conj.
就在那个时候,在...的时候
adv.
什么时候,...的时候
pron.
什么时侯,那时
when
when
AHD:[hwµn,wµn]
D.J.[hwen,wen]
K.K.[hwWn,wWn]
adv.（副词）
At what time:
什么时候：
When will we leave?
我们什么时候离开?
conj.（连接词）
At the time that:
在…的时候：
in the spring,when the snow melts.
在春天,当雪融化的时候
As soon as:
一…就…：
I'll call you when I get there.
我一到那里就给你打电话
Whenever:
无论什么时候：
When the wind blows,all the doors rattle.
只要风一吹,这门就吱嘎作响
During the time at which; while:
在…期间,当…时：
When I was young,I was sick all the time.
在我小时候我总是生病
Whereas; although:
虽然,尽管：
She stopped short when she ought to have continued.
尽管她应该继续下去,她却突然停住了
Considering that; if:
考虑到,如果：
How can he get good grades when he won't study?
他不用功的话怎么拿高分呢?
pron.（代词）
What or which time:
什么时候：
Since when has this been going on?
从什么时候起事情象这样?
n.（名词）
The time or date:
时间或日期：
Have they decided the where and when?
他们已经定下来地点和时间了吗?
Middle English
中古英语
from Old English hwenne * see k wo-
源自 古英语 hwenne *参见 k wo-
In informal style when is often used after be in definitions:A dilemma is when you don't know which way to turn.The construction is useful,but it is widely regarded as incorrect or as unsuitable for formal discourse.In formal style there is no alternative but to rephrase such definitions to avoid is when :A dilemma is a situation in which you don't know which way to turn.You are in a dilemma when you don't know which way to turn.
在非正式文体中when 常在定义中用在 be 后面：进退两难就是当你不知道该走哪条路的时候.这个结构是有用的,但被广泛认为它对正式交谈来说是不正确的或者是不合适的.在正式文体中没有替代词,只能改变措辞以避免is when ：进退两难就是这样一个你不知道该怎么办的处境.当你不知道你该做什么时你就处于进退两难的维谷了
when
中古英语 whenne＜古英语 hwenne
when,as,while这三个词都可以引出时间状语从句,它们的差别是：when 从句表示某时刻或一段时间 as 从句表示进展过程,while 只表示一段时间
When he left the house,I was sitting in the garden.
当他离开家时,我正在院子里坐着.
When he arrived home,it was just nine o'clock.
当他到家时,正是九点钟.
As he grew older,he became more intelligent.
随着他年龄的增长,他变得更有才智了.
While he was in London,he studied music.
当他在伦敦时,他学习音乐.
While she was typing the letter,the telephone rang.
当她在用打字机打那封信时,电话响了.