时态填空。
1. Listen! Someone _______ (sing) in the next room.
2. There _______ (be) an exhibition of art in the museum tomorrow.
3. Everyone in our class _______ (enjoy) music very much.
4. It's so cloudy. I think it _______ (rain).
5. We are looking forward to _______ (go) sightseeing.
6. When is the best time _______ (visit) your hometown?
7. The thief tried _______ (run) away but the policemen _______ (catch) them in the end.
8. Is it difficult _______ (finish) _______ (write) the article in one day?