You _________ a mask.
You must wear a mask.
You _________ your hands.
You must wash your hands.
You _________ a seat belt.
You must wear a seat belt.
You _________ in the classroom.
You mustn't eat in the classroom.
You _________ pictures in the museum.
You mustn't take pictures in the museum.
You _________ your cell phone in the cinema.
You mustn't use your cell phone in the cinema.
You _________ in the hospital.
You mustn't smoke in the hospital.
