Unit 4Unit 4 Dont eat in class Dont eat in class!Dont eat in the classrooms !A: Can we.?B: No , we cant,but we can A: So, dont ！A: Can we.?B: No , we cant, but we can A: So, dont ！Dont listen to music in classrooms or hallways!Dont fightFight with each othersA: Can we.?B: No , we cant, but we can A: So , dont . ！Do you have to ? Yes, we do. We have to No, we dont. We dont have to School rules1.Clean the classroom every day.2. Get to school before 7:00.3. Wear sports shoes for gym class.4. Be quiet in the library.5. Do homework on time.6.Wear a uniform at school.Does he have to ? Yes, he does. He has to No, he doesnt. He doesnt have to School rules1.Clean the classroom every day.2. Get to school before 7:00.3. Wear sports shoes for gym class.4. Be quiet in the library.5. Do homework on time.6.Wear a uniform at school. have/ has to dont /doesnt have to必须必须 ，不得不，不得不不必不必1.我们必须穿校服吗？我们必须穿校服吗？2.玛丽必须在餐厅吃饭吗？是的，她是。玛丽必须在餐厅吃饭吗？是的，她是。3.琳达，你不必在上午七点前到校。琳达，你不必在上午七点前到校。4. 他们在学校不得不做什么呢？他们在学校不得不做什么呢？5. 我们必须在图书馆保持安静。我们必须在图书馆保持安静。Do we have to wear a uniform?Does Mary have to eat in the dinning hall? Yes, she does.Linda, you dont have to get to school before 7 oclock.What do they have to do in the school?We have to be quiet in the library. dont have to + 动词原形动词原形 “ 不必或没必要做某事不必或没必要做某事”