Question

1. Complete the blanks with the following: don’t have to, doesn’t have to or mustn’t.

1. It is forbidden. You ___________________ do that.
2. You ____________________ ask my permission. You can do what you want.
3. You _________________ speak to the driver when the bus is moving. It's dangerous.
4. Help yourself to anything you want. You __________________ ask.
5. You _____________________ park here. There is a double yellow line.
6. Pay me back when you can. You ______________________ do it immediately.
7. It is optional. We _____________________ to go if you don't want to.
8. I'll tell you a secret. You __________________________ tell anybody else. Promise?
9. Whatever you do, you ________ click with the right mouse button or the program will crash.
10. Be on time! You ___________________ be late or we will leave without you.
11. He's a millionaire. He ____________________ work but he does because he enjoys it.
12. I like Saturdays because I ___________________ go to work.
13. This is very important. You _____________________ forget what I said.
14. It is very informal here. You ____________________ wear a tie unless you want to.
15. The train is direct. You __________________ change trains.
16. In boxing, you ______________________ hit your opponent below the belt.
17. I _____________________ wear a suit at work on Fridays. It's 'dressing down day".
18. In athletics, you ______________________ start before the gun is fired.
19. In bridge, you _____________________ look at other people's cards.
20. You ____________________ be mad to work here but it helps.

Answer 1

1. don't have to do that
2. don't have to
3. you mustn't
4. don't have to
5. mustn't
6. don't have to
7. don't have to
8. mustn't 
9. must
10. mustn't
11. doesn't have to
12. don't have to
13. mustn't
14. don't have to
15. don't have to
16. mustn't
17. have to
18. mustn't
19. mustn't
20. don't have to
Espero que te sirva. Espero 5 estrellitas tambien, suerte!