---- Do you know Jack well? ---- Certainly, we _________ friends since ten years ago.
Not only the students but also their teacher_______ the Great Wall before.
It is impossible for ______ little children to do ______ much work within 20 minutes.
He has spent as much time as he has _______ English in the morning.
We're not sure if it _______ tomorrow. If it _______, we won't go hiking.
His father has been _______ for three months because of the theft.