when 与as 之间的区别
当从句中的谓语动词是持续性的动作时,我们可以用 when 或 as;as 只能和延续性动词连用
When / As I was walking down the street, I noticed a police car in front of the bank
我顺着马路往前走时,发现银行门前停着一辆警车
当从句中的谓语动词表示瞬间动作时,只能用 when;when 可以和延续性动词连用,也可以和短暂性动词连用
He was on the point of leaving when someone knocked at the door
他正要走,这时有人敲门
如果表示两个短动作或事件同时发生,最常用的是 as 或 just as,或 when
Just as he caught the ball, there was a tearing sound
当他抓住球的时候,有一种撕裂的声音
I thought of it just when you opened your mouth
就在你要说话的时候,我也想到了
----再加一点个人理解:有 when 时,强调的是从句
As 时,强调的是主句
when,while 和 as 的区别 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,