问题补充:
I’m sure David when we get home.
A. is still sleeping
B. is to be sleeping
C. will still be sleeping
D. will have been sleeping
答案:
A. is still sleeping
B. is to be sleeping
(答案→)C. will still be sleeping
D. will have been sleeping
解析:考查时态:句意:我确定当我们到的时候,大卫将正在睡觉。When引导的时间状语,用一般现在时表示一般将来时,主语应该是将来范畴的动作,而且当我们到的时候,大卫是正在睡觉。选C。