when与while的差别

xyu201

简单来说, 当两个动作同时进行时,
较长时间的动作[强调持续]用(过去)进行式, 用while
较短时间的动作[强调瞬间]用(过去简单式, 用when
while + 延续性动词
when + 非延续性动词
当某一动词在延续性与非延续性上的语意都通时, while与when就可相通了.
e.g.
when I locked the door
while I locked(=was locking) the door

when and while are alike in the definition, but we usually use \"while\"
when the sentence is trying to show a \"long time\" or \"continuous\" action.
ex: I was taking a bath when you called me.
(call isn't a long time action, so we use \"when\")
  I fell down while I was walking on the street.
( \"was walking\" is a long time action, so we use \"while\" as an conjunction.)