Respuestas
Let's do it...
1. I mustn't eat junk food if I want to be healthy.
2. I have to be careful during the exam, otherwise I can't be successful.
3. We mustn't cross the street when it is red.
4. My mother doesn't have to get up early, because she doesn't work.
5. I have to inform my boss that I will be late to work.
6. My father always reminds me that I have to study more.
7. You don't have to wear uniform in this school, it is not necessary.
8. You mustn't make noise at night.
9. You have to be careful while you are driving.
10. We have to cut the trees if we want to earn money.
11. I have to get up early today, I have a meeting at 8 o'clock.
12. I have to leave home as soon as possible or I will be late to school.
13. I have to make a cake as it my son's birthday.
14. We have to clean the house after the party. Otherwise my mother will be angry.
15. They don't have to type the letters because they have enough time to finish them.