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

When do you have to be in bed?

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?