Look! The houses _________.
| A．is being built | B．are building | C．being built | D．are being built |
33. Nowadays, use____of certain waste materials to protect the environment.
| A．is making | B．will make | C．is being made | D．will be made |
32. I suggested that they set off early to avoid (避开) the traffic jam, ____________ no one responded.
| A．on which | B．to which | C．about which | D．for which |
31. How to solve the problem __________ in the meeting right now
| A．was being discussed | B．are being discussed |
| C．is being discussed | D．is going to discuss |
30. He’s making_____great progress in his lessons that everyone else in his class can’t believe it.
| A．So | B．very | C．such a | D．Such |
29. When I met him last year in Beijing, he was busy ___________ a new job.
| A．watching over | B．suffering from | C．hunting for | D．looking after |