精选优质文档-倾情为你奉上【文库独家】Unit 13 Were trying to save the earth!重点单词：Littler, bottom, fisherman, coal, ugly, advantage, cost, wooden, plastic, takeaway, cruel, harmful, industry, law, scientific, afford, reusable, recycle, gate, bottle, president,work, metal 重点短语:be full of 充满close down 关闭play a part in 扮演角色clean up 打扫卫生cut down 减少 instead of 代替make a difference 起作用，有影响used to 过去常lead to 通往hear of 听说be harmful to 对有害the food chain 食物链at the top of
