用on,因为是具体某一天 如:on a Monday morning, on a rainy day,如果没有Monday,就要用in. 所以是on Children's Day.
如果有“日”就用on 比如 on Monday,on Women's Day 如果没有“日”就用in 比如in January
用on,因为是具体某一天 如:on a Monday morning, on a rainy day,如果没有Monday,就要用in. 所以是on Children's Day.
of course ,on
on the Chindren's Day
on 特指某一天