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You mustn't / aren't allowed to eat sweet things.
What must/should you do if you get lost in the woods?
Should
The lawyer said we have to/ should sign the papers urgently.
have to
You mustn't/ don't have to iron the clothes - I'll do it.
don't have to/ don´t need to
Do I have to/must to finish the essay today?
have to/need to
You mustn´t/ don't have to smoke in hospitals.
mustn't
You can't/ shouldn't get a dog if you already have a cat.
shouldn't
What must/ should you do if you have a headache?
should
What needn't/ mustn't you take through customs?
mustn't
The cabin crew of an aeroplane must/ have to check if the passangers have their seatbelts fastened before take-off.
have to
If you're travelling from a Covid-19 area, you must/should have a negative test result.
must
