Надо составить 6 предложений с глаголами Can и must. В разных временах, помогите пожалуйста

I can try to explain

I must do my homework otherwise my mom will get mad

I could change everything, but i just didn't understand this.

I must obey the law

I can be a completely different person.

I must save my girlfriend from death.

You must do it.You must drink this medicine.You must eat it.

He can swim. My friends can dance salsa.He can not work all day round.She could not do it.