第四单元Dont eat in class重点短语1. on time 准时,按时 2. listen to 听3. in class 在课上 4. be late for 做迟到5. have to 不得不 6. be quiet 安静7. go out 外出 8. do the dishes 清洗餐具9. make breakfast 做早饭 10. make (ones) bed 铺床11. be noisy 吵闹 12. keep ones hair short 留短发13. play with sb. 和某人一起玩 14. play the piano 弹钢琴15. have fun 玩得高兴 16. make rules 制订规则 重点语法1、祈使句肯定的祈使句:(1) 实义动词原形+其他; (2) be动词原形+形容词+其他; (3) Let sb do sth. 否定的祈使句:(1) Dont+实义动词+原形; (2) Dont be+形容词