I can't/couldn't dance last week. I was sick.
couldn't
I couldn't/can't buy thetickets yesterday.
couldn't
You should/shouldn't eat fast food. It's not healthy.
shouldn't
Do you think you mum can/mustn't drive us to school on Monday?
can
You don't have to/mustn't study today because the test is next week.
don't have to
He couldn't/shouldn't be late to school every day.
shouldn't
I need help. I mustn't/should ask someone.
should
I can't/couldn't help you yesterday. I was busy.
couldn't
I need your advice. Should/Must I study more?
should
Before dancing you must warm on/up/for.
warm up
You don't have to/mustn't take your phone to school.
mustn't
You should/shouldn't stretch before running.
should
You don't have to/can't buy anything for the party. My mum has already bought everything
don't have to
Mike should/can stay in bed. He is sick.
should
We are lost. We should/mustn't ask for help.
should
I want to take part on/in a dance tournament.
take part in