1. MUST get a visa
2. SHOULD apply for a visa at least one month before you go
3. CAN'T stay there longer than your visa is opened to
4. SHOULD have a return ticket or you will have some problems to get the desirable date
5. NEEDN'T (DON'T HAVE TO) book a hotel room before you go, because there are usually a lot of vacancies
6. MUST get a work permit if you want to work there
7. SHOULD visit San Francisco, because people think it's the most beautiful city in America
8. NEED'T (DON'T HAVE TO ) change your money before you go, because there are many 24-hour banks
9. CAN hire a car because it's the easiest way to travel
10. MUSTN'T break the speed limits or you will have problems with the police
11. SHOULD visit your physician before you go to keep your health good far from your home
12. SHOULD have special injections before you go to keep your health good
