Exercise 1: Choose the correct form — don’t have to, must, mustn’t

Choose the correct modal expression to complete each sentence: 'have to', 'don’t have to', 'must', or 'mustn’t'.

You apologise; it isn't necessary.

You tell the boss what happened, or he'll fire you.

I wear a tie; I do it because I like wearing ties.

You smoke in here; smoking is not allowed.

I be late. It's the most important meeting of the year.

You go now; you can stay a bit longer.

Visitors to the zoo feed the animals.

You drive so fast; we have a lot of time.

We cook more; there's enough food.

You put salt in her food; the doctor said she can't eat salt.