The room is in a terrible mess; it _______ cleaned.
28.How can they expect to learn anything________they never listen?
27.Only when_______senior high school________to show a great interest in poems.
26.— Why are you still here? Everybody has gone to attend the lecture by the president. — Oh, I__________about it!
25.Mr. Duncan raised an unnecessary question__________-he then failed to find an answer.
24_______the sale usually takes place outside the house ,with the audience on benches ,_______chairs or boxes。