染雾when可用作并列连词，表示“这时(突然)”;while也可以用作并列连词，表示“而”“却”(表示对比);但as则没有类似用法。本文是大学网unjs.com小编精心编辑的when和while的相关内容，希望能帮助到你！
when有鉴于之意，如：
Why do you need a new job when you have got such a good one?
when 有虽然、尽管等让步之间，如：
They kept digging when they must know there was no hope to escape.
while 有对比之意，译为“而”。如：
That region has plenty of natural resouces, while this one has none.
while 有表示“部分同意”之意，如：
While she is likable girl, she is difficult to work with.
when和while 都有“在...时候”的意思。
主从句都是长时间的动作时，只用while;
While she read the paper, I cleared up the kitchen.
涉及到年龄和生活的不同阶段，用when;
When I was a child , I lived in London.
while不用于短时间的动作(这个大家应该都知道)
when和while的区别
(1)when即at the time that…，指「在……之时」，例如：
When I finished my letter, I posted it.
我写完信便寄出。
(2)while即at the same time that…，亦指「在……之时」，但其所表示的「同时」須有「持续性」，例如：
We must strike while the iron is hot.
我们必须趁热打铁。
(3)while不可用来表示「时间点」(a point of time)，例如：
错：While I finished my letter, I posted it.
因为动作具有「瞬间性」。
(4)while可用于对比(c
Mary is in blue while Cindy is in black.
玛丽穿蓝色衫，而仙蒂穿黑色衫。
(5)while又可表示「只要」(as long as)，例如：
While there is life, there is hope.
留得青山在，不怕没柴烧。
(6)再可表示「尽管」(although)，例如：
While I admit that the task is difficult, I don't think that it is impossible.
[when和while的区别]
