they will be back in three days.对划线部分提问划线部分 in three days
问题描述：
they will be back in three days.对划线部分提问
划线部分 in three days
答
How long will they be back?
答
when will they be back?
答
翻译中文是否应是在三天内.
答
when will they be back ?
答
How soon will they be back?