高二英语知识点Unit 8 First aid

高二英语知识点 Unit 8 First aid 1. don't have to (do sth.) (不必干某事) 2. lay, lie 的用法 3. fall off (跌倒; 减少) 4. knock off (one's feet) (把...击倒) 5. deal with (对付; 处理) 6. throw up (呕吐) 7. mouth-to-mouth (嘴对嘴) 8. out of one's reach (够不着) 9. ought to (应该) 10. pay attention to (注意) 11. take it easy (别紧张) 12. by mistake (弄误会) 13. hold up (举起)