when的用法：可作副词，when的含义为“什么时候”、“什么情况下”、“其时”、“当场”；可作代词，含义为“何时”；可作连词，含义为“在…时候”、“在…之后”、“在任何…时候”；还可作名词，含义为“时候”。
when的中文意思及用法介绍
when可作副词、代词、连词和名词四种词性，基本含义有“什么时候;何时;当时;什么情况下;何时;在…时候;当…时;在…期间;在…之后;时候。例句有：
1、When did you last see him?
你上次什么时候见到他的？
2、Sunday is the only day when I can relax.
星期日是我唯一可以休息的日子。
3、The last time I went to Scotland was in May, when the weather was beautiful.
我上次去苏格兰是在五月份，那时的天气好极了。
4、Until when can you stay?
你可以待到什么时候？
5、I loved history when I was at school.
我上学时喜欢历史。
6、Can you spare five minutes when it's convenient?
方便时能占用你五分钟时间吗？
7、How can they expect to learn anything when they never listen?
既然他们从不听讲，他们怎么能指望学到东西呢？
8、When eating a whole cooked fish, you should never turn it over to get at the flesh on the other side...
吃一整条鱼时，切忌把它翻过来去吃另一面的肉。
9、When I met the Gills, I had been gardening for nearly ten years.
遇到吉尔一家时我已经做了近10年的园艺工作。
10、When he brought Imelda her drink she gave him a genuine, sweet smile of thanks...
当他把饮料拿给艾梅尔达时，她真诚而甜美地向他微笑以示感谢。
11、He could remember a time when he had worked like that himself...
他还能记得自己一度工作起来也是那个样子。
12、How can I love myself when I look like this?...
我这个样子，怎么能对自己满意呢？
