By the time you arrive home,I _____ for several hours,so please d_英语解答

By the time you arrive home,I _____ for several hours,so please don't make a noise when you come in.
[A] shall be sleeping [B] shall have slept
[C] shall sleep [D]shall have been sleeping
为什么选D?清翻译整句

人气：272 ℃　时间：2019-08-21 19:52:29

解答

句意“你回家的时候我已经睡下好几个小时了所以你进来的时候请不要发出太大的声音”
因为是“已经睡下好几个小时”所以用have been 表示已经...了