You must come for lunch one day!
you can stay here until five o'clock.
We have to clean our shoes every day.
You must hit the ball into that area.
We shouldn't sell sweets in schools.
Emily has to wear glasses.
You have to have a passport to go to another country.
you should buy a dictionary.
You need to wear a face mask if you are going out.
You don't need to finish it now.
prohibition
advice
general obligation
a family rule
free from obligation
giving permission
a medical necessity
a sports rule
an invitation
an international rule