He can run as fast as he want
May I ask you for a favour
We do not have to go to work. These days are holidays
He can run as fast as he want
I must do it by myself. No one will help me and I will not ask for help
Katy must not ride a horse. She has serious problems with her back
He must take care of his parents! They are sick and poor!
You may take my suitcase if you need to travel abroad
I can play football.
He can skate and ski.