Modal verbs: have to, must
Modal verb ‘have to’ in different tenses:
Present tense:
She has to work every day.
She doesn’t have to work.
Does she have to work?
Past tense:
She had to work yesterday.
She didn’t have to work.
Did she have to work?
Future tense:
She will have to work tomorrow.
She won’t have to work.
Will she have to work?
Usage: You can use modal verb ‘have to’ in different constructions ‘I’m going to have to…’, ‘I might have to…’. It can be used as personal opinion or show objective obligation.
Modal verbs ‘must’ и ‘mustn’t
It’s a fantastic movie. You must watch it. = I think it’s important you to watch it, you need to do it. You must not touch this without permission. = It’s strictly prohibited to touch, so don’t do it.
Usage: ‘Must’ is similar to ‘have to’ and is used in giving your own opinion. ‘Mustn’t’ is strong prohibition. It is necessary that you do not do it.
Must & must have done
She has been working all day. She must be tired.
She didn’t come. She must have been tired.
She said she would come. Really? She must be joking.
She said she would come. But she didn’t come. She must have joked.
Usage: You can use ‘must’ to say that you believe something is certain. For past we use ‘must have done’ to say that you believed something was certain.
Difference between 'have to' & 'must'
We use 'have to' in Present, Past and Future tenses and other constructions. We use 'must' only in Present tense. It can express personal opinion or show objective obligation. It shows mostly your personal opinion.
Difference between 'don’t have to' & 'mustn’t'
'don’t have to' - You just don’t need to do it, but you can if you want. ‘Mustn’t’ is strong prohibition. It is necessary that you do not do it.
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Present tense:
She has to work every day.
She doesn’t have to work.
Does she have to work?
Past tense:
She had to work yesterday.
She didn’t have to work.
Did she have to work?
Future tense:
She will have to work tomorrow.
She won’t have to work.
Will she have to work?
Usage: You can use modal verb ‘have to’ in different constructions ‘I’m going to have to…’, ‘I might have to…’. It can be used as personal opinion or show objective obligation.
Modal verbs ‘must’ и ‘mustn’t
It’s a fantastic movie. You must watch it. = I think it’s important you to watch it, you need to do it. You must not touch this without permission. = It’s strictly prohibited to touch, so don’t do it.
Usage: ‘Must’ is similar to ‘have to’ and is used in giving your own opinion. ‘Mustn’t’ is strong prohibition. It is necessary that you do not do it.
Must & must have done
She has been working all day. She must be tired.
She didn’t come. She must have been tired.
She said she would come. Really? She must be joking.
She said she would come. But she didn’t come. She must have joked.
Usage: You can use ‘must’ to say that you believe something is certain. For past we use ‘must have done’ to say that you believed something was certain.
Difference between 'have to' & 'must'
We use 'have to' in Present, Past and Future tenses and other constructions. We use 'must' only in Present tense. It can express personal opinion or show objective obligation. It shows mostly your personal opinion.
Difference between 'don’t have to' & 'mustn’t'
'don’t have to' - You just don’t need to do it, but you can if you want. ‘Mustn’t’ is strong prohibition. It is necessary that you do not do it.
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