2. You don't have to have special qualifications.
It's obligatory to have It's not necessary to have
qualifications. qualifications.
3. You have to practice in a safe place before ironing on a mountain.
It's necessary to practice It's not required to practice
in a safe place first. extreme ironing.
4. You must iron sth bigger than a handkerchief.
It's obligatory to iron It's best if you iron
something. something bigger than a
handkerchief.
5. You mustn't use plastic or toy irons.
It's not correct to use a It's not allowed to use
plastic or toy iron. plastic or toys irons.
6. You should iron in an unusual place.
It's best if you iron in an You have to iron in an
unusual place. unusual place.
7. You shouldn't do extreme iron on your own.
If you go alone, it's OK. It's not allowed to do
extreme iron alone.
8. HAVE TO
To express responsibility or necessity.
In everyday conversations.
Softer obligation.
In the Present, Future or the Past.
9. SHOULD
To say what is best or right thing to do.
Softer necessity.
10. MUSTN'T
To express something is not allowed or forbidden.
11. NOT HAVE TO
To say that something is not necessary or that you are not
obliged to do it.
It expresses the idea that something is not required. It is
however, possible or desired.