I HAVE TO BE IN BED BY TEN OCLOCK 对BY TEN OCLOCK提问

问题描述:

I HAVE TO BE IN BED BY TEN OCLOCK 对BY TEN OCLOCK提问

BY TEN OCLOCK 是表示时间的状语,对此提问用表示“什么时候”的when提问
When do you have to be in bed?