What Are Must and Have to?
'Must' and 'have to' are two common modal verbs in English that are used to indicate that something is necessary or required. Both of these verbs are used in English, but 'have to' is generally more common among American English speakers.
Structure
Just like the other modal verbs in English, we use this pair with the base form of the verbs. Look at the following examples:
She
We
I
Do not forget to use 'to' in this modal verb.
Warning!
Unlike most modal verbs which have a single form for all persons, the form of 'have to' changes when used with a third-person singular subject.
She
These two modal verbs are also used in negative statements and questions.
To form negatives with 'must', simply add 'not' after it. The contracted form is 'mustn't'. For example:
I
To form questions, move 'must' to the beginning of the sentence, before the subject. Pay attention to the examples below:
We can also use 'must' in question tags. Look:
They must write their proposals,
Your friend must come with you,
Tip!
Please note that mustn't is only used in informal conversations and never in formal, written English.
To form questions with 'have to', you need an auxiliary verb. The subject and auxiliary verb are then inverted and 'have to' follows the subject. Pay attention to the example:
Here, 'do' is added as an auxiliary verb to form a question.
To form negative sentences with 'have to', you can add 'not' after the auxiliary verb 'do/does'. For example:
I
Uses
As mentioned above, 'must' and 'have to' are used in various contexts and situations. They can be used to:
- Indicate rules
- Suggest and recommend something
- Express something likely or logical
Indicating Rules
'Must' and 'have to' are both used to express a necessity or requirement, and to indicate that something is required to be done. Look at the following examples:
She
I
Suggesting and Recommending Something
'Must' and 'have to' can also be used to give suggestions or advice. When used in this way, they usually imply a strong recommendation. Study the following examples carefully:
Don't you think you
I think they
Expressing Something Likely or Logical
If we want to talk about a future event or something that is likely to happen, we can use 'must' and 'have to' as modal verbs. In this context, they can be used to express a high degree of probability or certainty. Look at the examples below:
Camping
It
Tip!
'Have to' is also used to show a sense of annoyance or frustration toward someone or something. Pay attention to the following examples:
It
Comments
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