背话题佳句：
1.It is high time for us to take measures to protect the environment.到了我们应该采取措施来保护环境的时候了。
2.In today’s world, many species become extinct or are threatened with extinction because of humans.
在当今世界中，许多物种灭绝了或者因为人类而面临灭绝的危险。
3.It takes many years to grow a tree but a day to cut it down.砍树容易种树难。
4.Better living conditions can really be reached on condition that the environment is well protected.
只有保护好环境，才能真正拥有更好的生活条件。
5.The terrible pollution has done great harm to us as well as to the surroundings.
可怕的污染已经给我们自己还有我们的环境带来了很大的危害。
6.Globalization makes the world smaller like a village where villagers have more opportunities to admire the beauty of other cultures.
全球化促成了地球村，让人们有更多的机会欣赏不同的文化之美。
背话题词：
1.develop renewable resources发展可再生资源
2.deal with rubbish properly 正确处理垃圾
3.improve one’s living conditions 改善居住条件
4.in the long term 从长远来看
6.have a considerable effect on 对……有极大的影响
8.achieve the highest growth 实现最大化发展
9.intercultural communication 跨文化交流