Exercise 2: Fill in the blanks with "couldn't/ have to/ might/ must/ ought to /shouldn't". 1. It's very cold today. Do you think it__________snow later? 2. You__________leave your door unlocked when you go out. 3. They__________have filled the car with petrol before they set off. 4. You don't__________pick me up at the station. I can get a taxi. 5. This is impossible, it__________be a mistake! 6. Tom__________have seen me because he walked past without saying "Hello". Exercise 3: Fill in the blanks with "must/ might/ can't" 1. Your mother__________be a great cook. You are always so keen to get back home to eat! 2. I don't know why I am so tired these days. I______________be working too hard. Or maybe I am not sleeping too well. 3. Do you know where Mike is? He__________be out - his car keys are on the table. 4. You seem to know everything about the theatre. You__________go every week. 5. To give the promotion to David was silly. He__________ know much about this company after only a year working here. 6. Go and look in the kitchen for your gloves. They__________be in there. 7. Oh, the phone is ringing. Answer it. It__________be Lisa. She always rings at this time. 8. Bob has been drinking that whiskey since early this afternoon. He_______be totally drunk by now. 9. That couple__________think much of this film. They're leaving already - after only 20 minutes! 10. That's the second new car they have bought this year. They__________be very rich!