when conj. when并列连词.= and then.表示“就在那时.突然 .常见以下句型中: (1) be doing...when...正在做--突然--I was wandering through the streets when l caught sight of a tailor's shop. (2) had done...when...刚做了--突然--I had just sat down when the light went out. (3) be about to do...when...刚要做--突然--I was just about to go swimming when our guide saw me and shouted at me. 【查看更多】
