Unit 2 Saving the Earth Topic 2 All these problems are very serious. Section A Teaching aims and demands 1. Master some new words and phrases : as a result, rude, behavior, in the beginning, day by day, die out, importance 2. Learn some useful sentences: (1)As a result, air pollution has become a serious problem. (2)Humans have come to realize the importance of protecting animals. 3. Learn the indefinite pronoun and adverb: (1) None of us likes pollution. (2) Dont spit anywhere in public. (3) Ev
