A: Choose the correct form of the verbs: can, could and (be) able to.
1. I really enjoyed staying with my aunt when I was a child because she always told me I could/was able to watch TV after 10 o'clock.
2. I couldn't have found/haven't been able to find my filofax for days now.
3. As soon as she arrived I could/was able to see from her face that she was depressed.
4. Why did I have to listen to you? I could have been/can be at home now instead of here.
5. You should have taken a taxi or you could phone/could have phoned me for a lift.
6. This refrigerator was $567 but I could/was able to get a discount because it was slightly damaged.
7. I have no idea where my sister is. She could/can be in the North Pole for all I know.
8. It is difficult to understand how miners work under such conditions. I can't/ couldn't.
9. She was able to be/could have been a star but she became a nurse instead.
10. I could/can drive but I can't ride a bike.
B: Choose the correct form of the verb: must/have to/mustn't/ needn't/don't have to.
1. You pay a month’s rent in advance. The landlord always insists on it.
2. You complete and return the completed form before Friday, 10th March.
3. In Britain, motorcyclists wear crash helmets.
4. You drink alcohol while taking these tablets.
5. You have a licence to have children.
6. You put out the rubbish. I can do that later.
7. Mr Brown work late in the office since he changed his job.
8. Mary has a weight problem. She knows she give up fried food if she wants to lose weight.
9. During the Antarctic expedition the explorers melt the snow to get drinking water.
10. You all remember to lock the door when you leave.
C: Choose the correct form of the verbs: must/can't/may/might.
1. You must be/ can't be very proud of your daughter winning the prize.
2. That play has been such a success. It must be / can't be easy to get tickets to see it.
3. You must be / must have been parched after carrying those heavy boxes. I must put the kettle on.
4. We thought you would have visited us when you were in town. I suppose you must be/ must have been too busy.
5. I'm sure you could pass the examination if you tried. You mustn't be/ can't be using the proper learning strategies.
6. Why did you work there? You might have enjoyed/ can't have enjoyed working in such an environment.
7. The shop may be delivering/must be delivering our new suite today.
8. You will have to go over the books again. You might have been concentrating/ can't have been concentrating when you looked at them the first time.
9. I just called the office but I guess they may have/ may be having a lunch break.
10. If you carry those heavy suitcases you must/ might injure yourself.
D: These sentences are wrong. Correct them.
1. I don't know who gave me this CD. It should have been my uncle.
2. She shouldn't be out so late. Look at her. She mustn't be more than fifteen.
3. They didn't want to come with us at first, but finally we could persuade them to come.
4. Will you like a cup of tea with your cake?
5. Mary hasn't to work on Saturdays any more.
6. ‘You must have been Anthony's brother. Hello, I'm Roger.'
7. I phoned yesterday and they said he's just left for a two day trip to Malibu.
8. We mustn't have booked seats for the show because the theatre is half empty.
9. I can't have to go to work yesterday so I stayed in bed till lunchtime.
10. You mightn’t have cooked all that food.