The room is in a terrible mess; it have been cleaned.
Harry, you can’t go out since you haven’t finished your homework; ______, there is going to be a heavy storm.
--- What a beautiful day! --- Yes, it is _______ that I’d like to take a walk.
—How about going out for a picnic on Sunday morning? —Hmm, ____.The weather is quite warm these days.
The driver ____ have drunk a lot before the accident, but I'm not quite sure of that.
When ____ to compare the education system of China and Britain, the professor gave no answer.