what do people usually do at或on.什么时候用at,什么时候用on啊?

问题描述:

what do people usually do at或on.什么时候用at,什么时候用on啊?
new year's day halloween easter may day cgildren's day national day mid(一横)autumn festival dragon boat festival spring festival 都应该是at,还是on啊?

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