Question

Have to do - Responsibilities

Use 'have to' in the past, present and future to express responsibility or necessity. NOTE: 'have to' is conjugated as a regular verb and therefore requires an auxiliary verb in the question form or negative.

Examples:

• I have to arrive at work at 9 sharp. My boss is very strict.
• We have to give him our answer today or lose out on the contract.
• You have to pass your exams or the university will not accept you.
• I have to send a report to Head Office every week.

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Must do - Obligations

Use 'must' to express something that you or a person feels is necessary. This form is used only in the present and future.

Examples:

• I must go to bed earlier.
• They must do something about it.
• You must come and see us some time.
• I must say, I don't think you were very nice to him.

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Don't have to do - Not Required

The negative form of 'have to' expresses the idea that something is not required. It is however, possible if so desired.

Examples:

• I don't have to listen to this. I'm leaving.
• You don't have to come if you don't want to.

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Mustn't do - Prohibition

The negative form of 'must' expresses the idea that something is prohibited - this form is very different in meaning than the negative of 'have to'!

Examples:

• I mustn't eat chocolate. It's bad for me.
• You mustn't phone me at work. We aren't allowed personal calls.
• They mustn't see us talking or they'll suspect something.

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Structure of Have to 

 

Structure of Must 

 

Comments

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thanks it was very helpful for me..