第1个回答 2019-01-03
as多用于口语中，引导持续性动词，侧重于两个动作同时发生，有“当……时候”，“一边……一边”或表示“随着”的含义
eg:He hurried home,looking bind as he went
As time went on,Einstein's theory to be correct
As he grew older,he began to go deaf.
while常引导延续性动词，表示的是时间段而不是时间点强调动作同时发生，相当于during the time
eg:He likes pop music,while I am fond of folk music.
when强调特定时间从句发生与主句动作之前用when,不可用while和as