Reformuler chacune des phrases suivantes en utilisant les modaux need ou must à la place de have to, de façon à conserver le sens initial de chaque phrase.
Alex has to clean his room.
You don't have to help me.
I have to go now.
She has to study hard.
We don't have to do the third exercise.
They have to be polite.
You have to be Jack.
He doesn't have to be so mean.