Lead-in

Environmental protection is undoubtedly a major issue that challenges the modern society with the development of new technologies and the explosion of world population．Our living conditions are getting worse and worse due to the destruction of our environment．Overuse of natural resources has affected ecological balance．Smoke and harmful chemicals from factories and garbage from cities have polluted our environment．Currently，environmental protection has drawn world wide attention and concern，for people have realized that humans are a part of nature and should be responsible for the ecological balance．Since this issue is closely related to all the individuals，measures should be taken to raise public awareness of the urgency of protecting the earth．Everyone should do their utmost to make the earth a better place to live on．(https://www.daowen.com)