on very cold morning对吗?
问题描述：
on very cold morning对吗?
答
on a very cold morning，定指用on the/this/that very cold morning
答
on a very cold morning
答
in 是泛指某个早晨
on 是可以指某人特定日期的早晨
所以要看你的上下文了
这里最好用 in a very cold morning