ShouldYou should call her, because she is not feeling well.
Have to/need to
Mom said I can't go out. I have to do my homework.
Must (vanuit 1e persoon)
You must buy a new car, because yours is dangerous.
Shouldn'tYou shouldn't jump off a bridge.
Don't have to/Don't need to
You don't have to pay me back right away. Take your time.
Mustn't
You mustn't run a red light.