what happened to you --- april fool is day a\ withb\ onc\ atd\ in为什么答案是b理由越详细越好,好的有赏

问题描述:

what happened to you --- april fool is day
a\ with
b\ on
c\ at
d\ in
为什么答案是b
理由越详细越好,好的有赏

是表示在具体的这一天里,整个这天,从日出到日落,所以用in

april fool 愚人节,指具体的某一天,用on