Must and Have to
'Have to' and 'must' have the same meaning and are used to express obligations. However, they are used in different situations and are not interchangeable.
Must and Have to
In this lesson, we will study two modal verbs: Must and Have to.
'Must' and 'have to' are used in the present to say that something is necessary or should be done. Have to is more common in American English.
Must
'Must' is a modal verb and it has different uses in English. It is used to talk about:
- expressing rules or laws
- expressing something likely or logical
- making suggestions and recommendations
Expressing Rules or Laws
'Must' can be used to express something necessary or very important like a rule or a law.
All applicants
You
In this case we are not referring to a law, but it is actually the rule of our house.
Expressing Something Likely or Logical
'Must' is used to say that something is likely or logical.
You
obviously, It is logical to get hungry after long hours of walk.
You
If you are talking about the past, use 'must have' + 'past participle'
He
She
Making Suggestions and Recommendations
'Must' can also be used to recommend that somebody do something because you think it is a good idea. This use is more common in British English.
You simply
We
Have to
'Have to' or 'have got to' is a modal verb and it is used to talk about:
- necessity and obligation
- giving advice or recommendation
- certainty
- an annoying event
Necessity and Obligation
Tip!
Must and have (got) to are synonymous in this use, i.e. expressing obligation and necessities.
In British English there is a difference between them. 'Must' is used to talk about what the speaker or listener wants, and have (got) to about other people’s wishes, rules or laws.
You
You
Past Obligations or Necessities
'Must' does not have a past form. To talk about the past, you use 'had to' or 'to have had to'.
I
Sara has
Future Obligations or Necessities
'Must' does not have a future form. To talk about the future you use 'will have to' or 'have to' if an arrangement has already been made.
She'll
I
Giving Advice or Recommendation
'Have to' in American English or 'have got to' in British English is used to give advice or recommend something.
You simply
You
Warning
As mentioned, modals do not need an auxiliary verb for questions or negation. But 'have to' is different. Questions with 'have to' are formed using the auxiliary verb 'do'.
Do we
You don't
Tip!
In negative sentences both 'must not' and 'don’t/doesn't have to' are used, but with different meanings. 'Must not' is used to tell somebody not to do something.
You
You
'Don't/doesn't have to' is used when it is not necessary to do something.
We don't
Certainty
'Have to' is used to express something that must be true.
Both 'must' and 'have to' are used to say that you are certain about something. 'Have to' is more common in American English.
There
If you want to talk about the past, use 'must have + past participle.'
Your trip
Annoying Events
'Have to' is used to talk about an annoying event that you think happens in order to annoy you, or that somebody does something in order to annoy you.
Just our luck. It
Does he
Review
'Have to' and 'must' is used to express obligations. They have many other functions. We can learn them sooner by examples.
must | |
---|---|
expressing rules or laws |
You |
expressing something likely or logical |
He |
making suggestions and recommendations |
You |
Have to | |
---|---|
necessity and obligation |
You |
giving advice or recommendation |
They |
certainty |
It |
an annoying event |
I wonder why it |