prohibition: "I ________ eat a lot of fast food."
I MUSTN'T eat a lot of fast food.
obligation: "I _____________________ before lunch."
I MUST WASH MY HANDS before lunch.
obligation: "You __________ wear a helmet to ride a bike."
You MUST wear a helmet to ride a bike.
prohibition: "I __________________ in class."
I MUSTN'T LISTEN TO MUSIC in class.
obligation: "I __________ go to bed early."
I MUST go to bed early.
prohibition: "I ______________________ in class."
I MUSTN'T use my mobile phone in class.
obligation: "I ________________ study for my exams."
I MUST study for my exams.
obligation: "We __________ wait outside."
We MUST wait outside.