25.I was about to leave for work ______the telephone rang.
| A．as | B．until | C．while | D．when |
—Who ______ it be that hasn't handed in his homework?
—It ______ be Bob. He handed it in yesterday.
| A．can; mustn't | B．must; can |
| C．can; can't | D．may; must |
Only those who have experienced hardship ______ well aware of what happiness means.
| A．can they be | B．they can be |
| C．can be | D．they can |
Even on a cold day he prefers ______ out to play football ______ at home.
| A．going; rather stay |
| B．going; to staying |
| C．to go; rather than staying |
| D．to go； rather than to stay |
It was unwise of him to ______ the unreliable data in his speech.
| A．refer to | B．add to |
| C．belong to | D．point to |
—Would you mind giving your advice on how to improve our business management?
—If you make ______ most of the equipment, there will be ______ rise in production.
| A．/；/ | B．the; a |
| C．/; a | D．the；/ |