Complete the dialogue with must/mustn't, should/shouldn't. Tom: Mum, I don't want to go to school. Mother: But you ____________ . Tom: The pupils don't love me. Mother: Well, you __________________ shout at them. You ____________ be polite and friendly. Tom: They ________________ use their mobiles but they do. They ___________ be late for school but they are. Mother: You ________________ be so angry. Try speaking to them. Tom: That won't help. I think I'm ill. I have a running nose ... Mother: Oh, no, come on, Tom. Shame on you! You are OK. You __________________ go to school. You're a teacher.