3 Circle the correct words. 1 A: You don't have to / shouldn't spend so many hours in front of the computer. It's bad for you. B: I know, but I have to / should finish this report. My boss wants it by 9 am tomorrow. 2 A: Is that my mobile phone ringing? B: Leave it. You mustn't / don't have to talk on your mobile phone while you're driving. 3 A: Sam! You almost knocked over that vase! You must / ought to be careful when you're playing the Wii! B: Oops! Sorry. 4 A: You may / must go now. We've finished for today. B: Thanks. I'll see you tomorrow. 5 A: I didn't get the chance to say goodbye to Zack before he left for the airport. B: Then, you have to / should send him a text message. 6 A: He's suffering from shoulder strain again. B: He really may / must see a doctor. 7 A: Ben has to / should share his laptop with his brother. B: Oh, poor him!