音标：[hwen]
conj. 当...的时候
ad. 何时, 什么时候
pron. 什么时侯
n. 时间
在线英汉词典

when的短语、例句：

hen interrog adv at what time; on what occasion 什麽时候; 什麽场合
When can you come? 您什麽时候能来?
When did he die? 他是什麽时候死的?
I don´t know when he died. 我不知道他是什麽时候死的.
When were you living in Spain? 您是什麽时候住在西班牙的?
Since when has he been missing? 他是从什麽时候失踪的? when, rel adv 关系副词 1 (used after time, day, month, etc 用於time、 day、 month等之後) at or on which 在那时; 其时
Sunday is the day when very few people go to work. 星期日是没什麽人上班的日子.
There are times when I wonder why I do this job. 有时候我也不明白我为什麽要做这个工作.
It was the sort of morning when everything goes wrong. 那天上午就是那样, 事事不顺心. 2 at which time; on which occasion 在那时; 当时; 当场
The Queen´s last visit was in May, when she opened the new hospital. 女王上次来访是在五月份, 她那时主持了这座医院的落成典礼. when, conj 1 at or during the time that 在...时; 当...时
It was raining when we arrived. 我们到的时候正在下雨.
When he saw her, he waved. 他一看见她就摆了摆手.
When visiting London I like to travel by bus. 我游览伦敦时喜欢坐公共汽车. 2 since; considering that 既然; 考虑到
How can they learn anything when they spend all their spare time watching television? 他们把所有的空闲时间都用来看电视了, 还能学什麽东西呢?