<P>what do you usually do (&nbsp;&nbsp; )Children's Day ?&nbsp;&nbsp; A&nbsp; &nbsp;at&nbsp;&nbsp; B&nbsp; on</P>
<P>what do you usually do (&nbsp; )Easter?&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; A&nbsp;&nbsp; at&nbsp;&nbsp; B&nbsp; on</P>
<P>请问选哪个，为什么？？</P>

具体到某一天用介词on

B    A

B A 最偷懒的方法，有day 的用on 没有的用at

on ,at

<P>同意楼上的</P>
<P>&nbsp;</P>

thanks a lot !

同意tongyi

谢谢,收益颇多!!!