Ⅰ. 选词填空
must, should, ought(n’t) to, don’t have to, couldn’t, mustn’t, needn’t, can’t, have to
1. You oughtn’t to go on working because you look so tired now.
2. I have no bike, so I have to go to the office on foot.
3. You needn’t/don’t have to come to the meeting if you’re too busy.
4. You mustn’t smoke in this part of the hospital.
5. I know things are hard with you, but you must try to get over the difficulties.
6. I didn’t see her at the meeting this morning; she couldn’t/can’t have spoken at the meeting.
7. You can’t imagine what difficulty we had walking home in the snowstorm.
8. You needn’t buy a gift, but you can if you want to.
9. You should/ought to follow the doctor’s advice. I think it will do good to you.
10. You ought to/should have given him some advice, for he was too upset at that time.
