表示事件时的用法区别:in时间长;on某点;at时间短。
表示地点时的用法区别:at强调点;on强调面;in强调在里面。
表示方位时的用法区别:介系词in表示的方位是在某事物的内部,占去某物一部分。
in
1、It startled me to find her sitting in my office.
我一进办公室,发现她坐在里面,把我吓了一跳。
2、We were locked in.
我们被锁在里面了。
on
1、I got to know David on the second day of middle school.
我在上中学的第二天就认识了大卫。
2、Several workers interviewed during a factory visit on Friday said they were also doing overtime each Saturday.
在上周五参观该工厂期间,一些接受我们采访的工人表示,他们每周六也要加班。
at
1、I called in at my local on the way home.
我回家途中去了我住处附近的酒吧。
2、The children are at different stages of development.
这些孩子处于不同的成长阶段。