when表示“当”时,怎样用?

Question

when表示“当”时,怎样用?

Answer 1

前面的分句的谓语用 be doing sth / had done sth / be about to do sth ,when译“这时”或“这时突然”
He had left the room when the telephone rang .他刚走出房间,这时电话响了.
He was walking along the street when the accident happened .我正在大街上走,突然事故发生了.
He was about to take away the wallet when the manager came in .他正要拿走钱包,这时经理进来了.