You must wear a seatbelt. They must

Obligations in the past and in the future

To describe an obligation in the past, the only form possible is the past of ‘have to’ which is ‘had to’. So the simple past form of ‘must’ is ‘had to’. The structure is the same for all subjects:



For example:

I had to wait a long time for my bus.

We didn’t have to use our passports. They accepted our ID cards.

Did you have to pay a fine when the police stopped you?

The doctor told her she had to lose weight.

They had to queue up for two hours to get through security. They almost missed their flight.

You had to do a lot of conference calls in your last job, didn’t you?

We can also use ‘have to’ in other tenses, like the present perfect form when we want to describe recent obligations or obligations within an unfinished time period. For example:

I’ve had to work a lot this week.

She’s had to leave early because her daughter is sick.