MODALS OF OBLIGATION, PROHIBITION AND NECESSITY.

We use have (got) to, had to and must when we talk about ...

• necessity.

• obligation

• no obligation

• prohibition

We use: don't have to / haven't got to and didn't have to to to talk about ( ...)

• necessity.

• obligation

• no obligation

• prohibition

We use: mustn't when we talk about ( ...)

• necessity.

• obligation

• no obligation

• prohibition

We use: need to and needed to when we talk about ( ...)

• necessity.

• obligation

• no obligation

• prohibition

We use: don't need to and didn't need to when something is not necessary.

• lack of necessity.

• obligation

• necessity.

• prohibition

At my school, we ... wear a uniform. We can wear what we like.

• must

• have to

• don't have to

You ... wear a cap in the swimming pool. It's obligatory.

• have to

• mustn't

• had to

We ... bring a packed lunch. The school provides it.

• don't need to

• must

• mustn't

Students ... bring their dictionaries to school yesterday.

• mustn't

• must

• needed

HOME LIFE : My host "parents" think it's acceptable to saty put until 10.30at the weekend. We ... home by then or there's trouble!