El verbo "must" es un verbo modal que significa “deber” y mustn't es la negacion.
osea que solo ppiensa en lo que no debes hacer y lo que debes hacer en clase y ya pasalo a ingles. por ejemplo
i must pay attention in class
i mustn't eat in class.
i must listen to my teacher
i mustn't urgue with my teacher
i mustn't talk in class...
espero que te sirva un poco...
*debo prestar atencion en clase.
*no debo comer en clase.
*debo escuchar a mi profesor.
*no debo hablar en clase.
*no debo discutir con mi profesor.
I must to pay attention
I must to study
I must to obey my teacher
I must to respect my clasmates
I must to be quiet
I must to work hard
I must to be seated
I must to do my homework
I must to respect my teachers
I must to get early to class
I mus´nt get late to class
I mus´nt speak up in the class
I mus´nt play with the ball
I mus´nt argue with my classmates
I mus´nt argue with my teacher
I mus´nt be talkin
I mus´nt call by phone
I mus´nt run in the classroom
I mus´nt cheat on the exams
I mus´nt offend anybody
