must/mustn't

______ I wash the car now?I can do it later.

We_____ leave.We are late for school.

You _____ talk in the library.

You ____ feed the animals in the zoo.

You ____ take pictures in the museum.

You _____ watch TV all day.It's bad for your eyes.

Ann,you ____ study hard.The test is difficult.

You ____ talk in class.

She_____ clean her room.It's a real mess.

You _____ be quiet at the lesson.