Have to / Must
Subject + have / has to + present tense verb phrase
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Subject + must + present tense verb phrase
You have to wear a uniform.
I must be at work by 9am.
Have to / must - explain
General rule
Have to = very important, something bad will happen if you do not do it, you have no choice.
Must = something that would be very good if you did it. You have a choice, but you should do it.
You have to wear a uniform.
If you did not wear a uniform, you would lose your job.
I must be at work by 9am.
Being at work by 9am would be be good.
Example 1
A story
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Monday: David arrives at work at 9:05am. Gary is David's boss.
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Gary: David, you must be at work by 9am.
David: Yes, Gary. I will tomorrow.
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Tuesday: David arrives at work at 9:10am.
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Gary: David, remember you must be at work by 9am.
David: Sorry Gary, the trains were late.
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Wednesday: David arrives at work at 9:07am.
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Gary: David, you are late again. You have to be at work by 9am tomorrow. Do you understand?
David: Yes, Gary. Will do. Sorry.
On Monday and Tuesday David was late. Gary said he 'must be' at work by 9am. Sometimes people are late, so it would be good if David made sure he was on time. However, David was late on Wednesday as well. Now, something bad would happen if David was late again. This is why Gary said 'have to'.
Example 2
I have to do my homework.
I will get detention if I don't.
I must do my homework.
I can play computer games when I do.
He 'has to' do his homework.
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Something bad (detention) will happen if he does not do it.
He 'must' do his homework.
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Something good (computer game) will happen if he does it.
Example 3
I am moving to London so have to study English.
He is moving to London. People speak English there. To be understood he has to speak English.
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I would be bad if he did not.
I like English but I don't have time to study. I must study more.
English is her hobby. She does not have time to study. Studying more would help her improve.
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She must study English.
Have to / must - practice
Have to: look after children
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I have to look after children.
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Must: wear smart clothes
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I must wear smart clothes.
Teacher
Have to: help customers, wear a uniform​​
Answer - She...and...
She has to help customers and wear a uniform.
Must: smile
Answer - She
She must smile.
Shop assistant
Have to: write accurate notes, take care of patients​​
Answer - She...and...
She has to write accurate notes and take care of patients.
Must: be kind
Answer - She
She must be kind.
Nurse
Do not have to / Must not - explain
Subject + do not have to + present tense verb phrase
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Subject + must not + present tense verb phrase
Do not have to
You don't have to help me.
This means:
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it is okay if you do not help
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it is not important to help
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not helping is okay
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She does not need help.
Must not
You must not talk! This is a library.
This means it is a rule. It would be very bad if you broke the rule.
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You must not talk in a library.
Examples
In a park:
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You must not litter.
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You must not smoke.
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You must not have a barbecue.
In a swimming pool:
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You must not run.
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You must not splash.
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You must not jump in.
Have to / Must / Do not have to / Must not
must not
do / does not have to
must
have to
Bad if you do.
Okay if you do not.
Good if you do.
Bad if you do not.
Fiona's diary
23rd June
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Mr. Smith gave the class a project to do for the 30th June. I must not forget to do it!
must not forget = it would be bad if I forgot
24th June
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I wanted to start my project today but went swimming instead. It was great fun. It's okay - I don't have to do it yet.
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Tomorrow I'm going shopping with my friends. I have to think about what to wear. I might wear a yellow dress because it will be hot.
don't have to do it yet = doing it is not important; it's okay that I don't do it
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have to think about what to wear = it would be bad if I did not think about what to wear
25th June
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Shopping was fun but tiring. I am exhausted. I must start my project tomorrow or I will not finish it.
must start = it would be good if I started
27th June
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I was in bed all day yesterday. I was ill after shopping so much. I have to be better tomorrow - there's a party at a school.
have to be better tomorrow = it would be bad if I did not get better
28th June
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I just got back from the party. It was so good! The music was fantastic and I danced all night.
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Tomorrow I have to do my project.
have to do my project = it would be bad if I did not do my project
29th June
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I am still working on my project. I have to finish it in the morning and hand it in to Mr. Smith.
I should have started it earlier.
have to finish it = it would be bad if I did not finish it
Don't have to - practice
James
Sophie
Sophie: I'm not feeling very well.
James: I'm sorry to hear that. Can I get you something to eat?
Sophie: Thank you but you don't have to.
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James: I'm going to the supermarket. Would you like some medicine?
Sophie: You don't have to buy any, I have some at home.
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Sophie: I'm going to make a cup of tea. Do you want one?
James: You don't have to do that; you're ill. Let me make it.
Dooesn't not have to - practice - Job / verb / clue
Office / work / weekends
Answer - An office worker...
An office worker doesn't have to work weekends.
Chef / serve / customers
Answer - A chef...
A chef doesn't have to serve customers.
Police officer / be / tall
Answer - A police officer...
A chef doesn't have to serve customers.
Singer / be / young
Answer - A singer...
A singer doesn't have to be young.
Nurse
Vocabulary - Verbs
Vocabulary - Nouns
Everyone doing the same thing, wears the same uniform.
must not
do not have to
must
have to
Bad if you do.
take care of patients
look after patients
give wrong medicine
help patients
change the bedding every day
wear a uniform on days off
wear a uniform at work
Okay if you do not.
Good if you do.
Bad if you do not.
Answer - A nurse
A nurse has to take care of patients.
Answer - A nurse
A nurse has to look after patients.
Answer - A nurse
A nurse must not give the wrong medicine to patients.
Answer - A nurse
A nurse must help everyone.
Answer - A nurse
A nurse does not have to change the bedding every day.
Answer - A nurse
A nurse does not have to wear a uniform on days off.
Answer - A nurse
A nurse has to wear a uniform at work.