we have social study class on Monday morning 还是 we have social study class in Monday morning到底是用in还是用on,

we have social study class on Monday morning 还是 we have social study class in Monday morning到底是用in还是用on,
we have social study class on Monday morning 还是 we have social study class in Monday morning
到底是用in还是用on,

we have social study class on Monday morning 还是 we have social study class in Monday morning到底是用in还是用on,
具体的某一天早上用On

on

用on
on monday
in the morning
连起来时用
on monday morning