Our professor told us that salt water _____ at a lower temperature than fresh water.
| A．is freezing | B．was frozen | C．freezes | D．froze |
The airport ___next year will help promote tourism in this area.
| A．being completed | B．to be completed |
| C．completed | D．having been completed |
Nowadays people are more concerned about the environment ___ they live.
| A．what | B．which | C．when | D．where |
____ which university to attend, the girl asked her teacher for advice.
| A．Not knowing | B．Knowing not | C．Not known | D．Known not |
He is so busy. He cannot afford enough time with his son ____he wants to.
| A．even if | B．as if | C．because | D．before |
____you said at the meeting describes a bright future for the company.
| A．When | B．How | C．What | D．That |