Choose the correct options.
1.rabbits can't / must fly.
2.you could / mustn't forget your book. you'll need it.
3.last year i must / had to learn chinese.it was really difficult.
4.i've been learning english for seven years,so i can/ have to speak it quite well now.
5.you should / mustn't try harder in class.
6.my mum can't / couldn't swim when she was a child.
7.you mustn't / don't have to wash your hair every day. twice a week is enough.
8.we had to / could see the sea from the house where we stayed last summer.
9.she must / shouldn't remember her hockey stick today because she's playing in a match.
10.i have to / can't study tonight because we have an important test tomorrow.
11.you can / shouldn't swim in the lake. it's very danderous.
12.my grandad mustn't / didn't have to study science at school.
1. can't
2. mustn't
3. had to
4. can
5. should
6. couldn't
7. mustn't
8. could
9. must
10. have to
11. shouldn't
12. didn't
2 mustn’t
3 had to
4 can
5 should
6 couldn’t
7 don’t have to
8 could
9must
10 have to
11 shouldn’t
12 didn’t have to