你何时回来？ ！有确定时间了吗？ ！

Have you decided when you are coming back?

youdao

你知道他何时回来吗？

Do you have any idea when he'll be back?

youdao

你随时都可以掉头回来，也可以在一星期中任何一天任何时刻上路，这样你就不用受繁忙时段（或许整个工作日都是）的交通之苦了。

You can turn back any time you want, and you can go any day of the week at any time, since you won’t have to compete with rush hour (or even weekday) traffic.

youdao