Unit 11. the average age / height平均年龄/身高2. make things dirty and unhealthy使东西变的得脏而不健康3. air pollution空气污染4. sound / noise pollution噪音污染5. water pollution水污染6. magnolia trees白玉兰7. be known/ famous as被作为知晓8. pollution fighters抗污染的战士fighters against pollution9. produce harmful gas产生有害气体 10. pass information to one another / each other相互之间传递信息11. collect sth. for为收集某物12. a class project on pollution在污染方面的课题13. be interested in在方面有兴趣14. living things o
