Must and Have to for intermediate learners

'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 English Grammar

What Are Must and Have to?

'Must' and 'have to' are two common English modal verbs used to indicate that something should be done or to necessitate an event. Both of them are used in English but 'have to' is more common among American speakers.


Just as the same as the other modal verbs in English, we use this pair with the base form of the verbs. Look at the following examples:

She must stop this mess at once.

We must go to the book store and change it.

I have to leave you for good.


Be careful that you do not forget to use 'to' after the modal verb.

She has to learn German if she wants to travel to Germany.

As you can see, when using a third-person singular pronoun, this modal verb is changed accordingly.

These two modal verbs are also used in negative statements and questions. Pay attention to the sentences below:

I must not talk to her like that.

Must I study that hard?

We can also use 'must' in question tags. Look:

They must write their proposals, mustn't they?

Your friend must come with you, mustn't he?


Please note that mustn't be only used in informal conversations and never in formal, written English.

I don't have to surrender to you sir.

Do I have to eat lunch at this hour?

As you can see, when using 'have to' in such sentences, we should add 'do' or 'does'.


As it was mentioned above, these two are used in various contexts and situations. Below is a list of their important uses:

  • Indicating Rules
  • Suggesting and Recommending Something
  • Expressing Something Likely or Logical

Indicating Rules

These two modal verbs are used to talk about a necessity and something that must be done. Look at the following examples:

She must stop running from her problems.

I have to complete my novel this week.

Suggesting and Recommending Something

These two modal verbs can also be used when we are trying to suggest an idea to someone or give them a simple piece of advice. Study the following examples carefully:

Don't you think you have to try the shoes on first?

I think they must avoid all this drama.

Expressing Something Likely or Logical

If we want to talk about a certain event, or something likely to happen, we can use these two modal verbs. Look at the examples below:

Camping must be a fun activity.

It has to be her then.


As mentioned above, 'have to' is also used to show a sense of annoyance to someone or something. Pay attention to the following examples:

Does she really have to be that loud?

It had to start snowing the moment we stepped foot on the jungle.

Here, the sentence shows that he/she was hurt by someone or something, there is no force or necessity here.


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