MUST & HAVE (GOT) TO  Must expresses internal obligation, e.g. I/we must remember to go to the optician’s; Have to expresses external obligation, e.g. I/we have to start wearing glasses. In AmE have got to (usually pronounced gotta) is often preferred over have to or must. A command can be seen as an appeal for some sort of internal obligation on the listener’s part. The power relationship of speaker to listener (register) is important {have to is also possible): You must be home by midnight. You really must leave now, darling. The unacceptability of haven’t to as imperative results in a high frequency of mustn’t: You mustn’t be home late. You haven’t to be home late. You mustn’t tell a soul. Must is also often used in written instructions, or as a formal statement of a rule: All candidates must carry valid identification. Practice Complete these sentences with must, mustn’t, have to, or don’t have to. 1. There’s a funny noise coming from my car. I really ___________ take it into the garage. 2. You really ________be late again. If you are, you might find yourself looking for another job! 3. Thank goodness I_____________ write in English at work! My spelling is awful. 4. The flight’s at ten, and we ___________ check-in at least ninety minutes before. 5. If you get the chance, you really ___________go and see the Van Gogh museum while you’re in Amsterdam. 6. We’re having a leaving party for Anne-Marie and we want it to be a surprise, so you ___________tell her, whatever you do. 7. We ____________be at the hotel by 9.30. Otherwise, the coach will leave without us. 8. I really __________make an appointment at the dentist’s. It’s over six months since I last went. Had to / didn’t have to Put these sentences into the past. 1.I must be at the station by 6.30 tomorrow morning I ______________________________ this morning. 2. I don’t have to be home early today. I_____________________ yesterday. 3. I have to have a word with my boss later . I_________________________ last week. 4. We must get our passports renewed . We _______________________last summer. 5. We have to get a taxi. We _________________ last night. 6. I must e-mail the report by twelve. I __________________this morning. 7. We don’t have to stay till the end, The meeting didn’t finish until eleven, but we _____________________________________ . 8. I must pay my phone bill this week or I’ll be cut off. I _____________________last week before they cut me off.