Modal Mastery

No 'to' before the verb

Negative forms with 'not'

Can

Base form after modals

Incorrect verb forms after modals

Could

Permission

Obligation

Ability

Using 'must' for suggestions

Might

You must finish your homework.

Confusing 'may' and 'might'

She can swim.

Possibility

May

Prohibition

Must

May I come in?