—Can Professor Li be in the laboratory?
—He ______ be； I saw him there half an hour ago.
| A．can | B．must |
| C．might | D．need |
The government has to close those small factories to prevent the water of the river___.
| A．from polluting | B．polluted | C．polluting | D．being polluted |
Along with the letter was his promise _____ he would visit me this coming May Day.
| A．that | B．which | C．what | D．whether |
第二部分
I．单项选择（共15小题，每小题1分，满分15分）
Don’t give up halfway, Andy. You’ll succeed ________ if you keep on working
like this.
| A．in return | B．on time | C．by the time | D．in time |
If we go on using energy so wastefully, __________ are that our oil wells will be dried up before new energy sources can be found to replace oil.
| A．chances | B．opportunities | C．questions | D．problems |
— They are quiet, aren’t they?
— Yes. They are accustomed ______ at meals.
| A．to talk | B．to not talk | C．to talking | D．to not talking |