Completa le frasi utilizzando MUST oppure MUSTN'T ma scegli quale usare in base alle regole che ti hanno dato i tuoi genitori.
You...tidy up your room. / You...smoke. / You...do your homework. / You...play with fire. / You...be home on time. / You...cheat in a test. / You...turn the music too loud. / You...help in the house. / You...annoy your little sister. / You...bite nails.