'We have to finish this by the end of August.'
The verb to have to has the same function as a modal auxiliary verb and has different uses.
affirmative: subject + 'have to' + bare infinitive
You have to go. He has to go
negative: subject + 'do not' + 'have to' + bare infinitive
You don't have to go. He doesn't have to go.
interrogative: 'do' + subject + 'have to' + bare infinitive
Do you have to go? Does he have to go?
Note that unlike modal auxiliary verbs, to have to takes the usual forms of 'have' depending on the subject and the tense. We avoid contracting have to.
Have got to is a common alternative to have to in informal conversation in the present tense. It is usually contracted.
affirmative: subject + 'have got to' + bare infinitive
You've got to go. He's got to go
negative: subject + 'have not got to' + bare infinitive
You haven't got to go. He hasn't got to go.
interrogative: 'have' + subject + 'got to' + bare infinitive
Have you got to go? Has he got to go?
Note that although have got to can be used for any of the uses of have to, it is less likely to be used
for obligation. It is also more common in specific than general situations. For example:
We have to do one hour of elearning before our telephone meetings.
I have to/'ve got to do my elearning this morning - I've got a meeting later.
Use | Examples |
Necessity
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We've got to finish this by Friday.
We don't have to get here so early tomorrow - the meeting was postponed.
You haven't got to go to the doctor's for aspirin. You can buy them directly from the chemist.
You have to work hard if you want to succeed.
The company has to improve its sales figures next year.
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Obligation - when there is a rule or requirement.
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We have to wear a suit and tie to work when we have visitors.
You don't all have to be there - just one person from each team will be enough.
You haven't got to wear a suit and tie to work on Friday. You can wear jeans instead.
Visitors have to report to reception.
All drivers and passengers have to wear seatbelts.
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Strong advice, including to oneself.
We cannot use don't have to here. |
You have to go the doctor's - you're not getting better.
I have to remember to phone him back.
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Deduction - when we believe something is certain.
We cannot use don't have to here. |
That's got to be Carole at the door - I'm expecting her.
You have to be better at English now - you work for an English company.
"How old is she?" "Well, she started work a few years before me so she has to be about 40."
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To talk about the best or right thing to do. [a strong opinion]
We cannot use don't have to here. |
Banks have to tell customers in advance about charges.
The government has to reduce spending.
We have got to protect the environment.
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These do not have the same meaning.
'Mustn't' suggests that something is prohibited or it is not the right or recommended thing to do.
'Don't have to' means that something is not necessary or obligatory. So it can be the opposite of both 'have to' and 'must'.
For example:
Mustn't | Don't have to |
Employees mustn't wear jeans to work. [forbidden]
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You don't have to wear jeans to work. [it is not necessary - you have a choice]
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You mustn't eat that - it will make you fat. [advice]
You mustn't eat that - it's not acceptable in this country. [forbidden]
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You don't have to eat that - you can give it to the cat if you don't like it! [not necessary]
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You mustn't change trains - you'll get lost. [advice] |
You don't have to change trains because it's a direct service. [not necessary]
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You mustn't make eye contact with Japanese people. |
You don't have to make eye contact with Japanese people.
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It might rain later but you mustn't take an umbrella. |
It might rain later but you don't have to take an umbrella if you don't want to.
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It rained on Saturday so we had to cancel the barbecue.
When I worked in a factory, everyone had to wear protective clothing.
They didn't have to pay a deposit.
Did you have to phone him to confirm?
Have to can be used in several future forms. For example:
All delegates have to arrive at the conference one hour before it begins.
Tom can't come to the meeting so we'll have to arrange another date.
We're going to have to postpone the launch until next month.
Do you have to have vaccinations if you go to North Africa?
That's got to hurt!
Tonight has been great - you have to come and see us again soon.
I've just got to fix this. Then I'll get ready to go out.
You'll have to do better than this if you want to pass the exam.
'Have to' can be used with other modal auxiliary verbs. For example: I might have to pick him up from the airport later. I shouldn't have to write this report; it's usually Jan's responsibility.
The present continuous
'Have to' is not normally followed by the present continuous. It is more usual to use 'must'.
For necessity we can use 'have to' in the present continuous. For example:
We're having to repaint the kitchen.
He's having to work late all this week.
'Have to' is also possible in the present perfect and past perfect:
I'm going to Japan for the first time next week so I've had to learn some Japanese expressions.
I've been having to do all of Janette's work while she's been on holiday.
Two years ago I went to work in England for six months. Before that, I hadn't had to speak English since I was at school.
He'd been having to deal with this on his own until we employed an assistant.
These have the same general meaning but are sometimes used in different ways.
For necessity, 'must' is often used in formal situations - spoken or written. For example, in a formal announcement or a written notice. In everyday conversation, we use 'have to'.
If you hear 'must' in conversation, it is being used emphatically or as advice, including to oneself.
For example:
'Have to' for necessity [conversation] | 'Must' for necessity [formal or emphatic] |
"We have to wear protective clothing at work."
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All visitors to this site must wear protective clothing.
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"Oh, look. We have to show our ID cards before we go in."
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ID cards must be shown before entering.
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"Sorry, but I have to leave the meeting early today. Is that OK?"
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"Sorry, but I must leave the meeting early today. Is that OK?" |
"Arnaud won't be at the meeting next week. He has to go to Paris to see a client." |
"Arnaud won't be at the meeting next week. He must go to Paris to see a client." |
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"You really must eat less if you want to get into that dress for the wedding."
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"You must finish that before Friday or we'll lose the contract."
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| 'Must' for advice - telling yourself what you should do. |
"I have to go to the bank today." [I have an appointment or I need to get some money etc.]
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"I must go to the bank today." [I should have gone last week but I've been busy and I keep postponing it. I'm going on holiday tomorrow so if I don't get my foreign currency today, it will be too late!]
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"The doctor told me I have to stop drinking wine while I'm taking these tablets."
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"I must stop drinking wine every evening - I'm not sleeping very well at the moment!"
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"I have to find a new job by January when this contract finishes."
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"I must start looking for a new job - I just don't enjoy working here anymore."
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"I mustn't forget to call Louise today."
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