Must
You must wear a crash helmet on a motorbike. It is the law.
Have to
You have to stamp your ticket when you get on a bus in Rome
Mustn't
You mustn't drive a car without a license.
Can
You can either take the bus or the metro.
Could
You could take a taxi if you are in a hurry.
Should
Should our children be taught to swim at school?
Ought to
You ought to ask a lawyer's advice.
Had better
We had better stay indoors today.
Can
I can ride a horse. I had lessons when I was a child.
Could
In high school, she could beat anyone in the running race.
was/were able to
He was able to get a really good price on the car.
Will
I'll drive you to the station if you want.
Can
Can I borrow your pen?
May
May I open the window?
Could
Could you carry this for me? It's too heavy.
Will
Will you answer the phone please. I'm busy.
Would
Would you get me a newspaper when you go to the shops please?
Shall
Shall I get pizza for dinner tonight?
We shall meet at the station at 7pm.
Might
He might be in the office on the Tuesday, but I'm not sure.
I heard what might have been an explosion.
May
We may have some rain today.
The chaos may have contributed to the deaths of up to 20 people.
Could
He could have made a fortune as a lawyer.
He was jailed five years ago and could be released next year.
Must have Vpp
He must have been in the office. His car was there.
Can't have Vpp
He can't have been at work on Friday. I saw him at the stadium.
Should have Vpp
You should have spoken to your lawyer before deciding.
I'm really tired today. I shouldn't have stayed awake so late last night.