My thumbs hurts when I send messages
You don't have to use your cellphone
I have broken my leg, what must the doctor do?
The doctor must ...
I have lots of spots on my face
You must/have to wash your face, go to a doctor.
I feel sick when I eat cookies and chocolate
You musn't eat cookies and chocolate, you must drink more water and healthy food.
I am sad, can you tell me what to do?
...
I often get earaches
You must check your ears, you have to clean your ears, you mustn't use earphones
I am stressed, What can I do?
...
I get lots of headache
You must/have to drink water, sleep, take a pill.
I have spots on my face, what must the doctor do?
The doctor must....
I have fallen over and hurt my knee
You must to put a band-aid