1. You must be 18 before you can drive in Spain. 2. You shouldn't go to bed so late. It's not good for you. 3. You don't have to wear a school uniform in most Spanish state schools. 4. You needn't come. I can do it without you. 5. You mustn't copy during exams. 6. You don't have to be very tall to play football. 7. You mustn't be a good writer to win the Pulitzer Prize.