You must use the iron to iron your clothes.
Obligation
I have to clean my bedroom every Saturday.
Responsibility
You must not mix electronics and water.
Phohibition
I don´t have to wash dishes after I cook.
Not required
You must wash with cold water. Says the label.
Obligation
My mom has to cook dinner for us every night.
Responsibility
You must not wash it with hot water.
Prohibition
You shouldn´t eat without washing your hands first.
Advice
I don´t have to set my alarm before 6. I work at 8:00.
Not required
You should set an alarm off to be on time for class.
Advice
You should wash your clothes after one use.
Advice
My daughter has to unload the dishwasher everyday.
Responsibility