求翻译，在线等，紧急！谢谢！

In the 21st century, the young shoulders with many of our responsibilities. Today I want to tell you is the 21st century youth to the environment.
The weeks, we have only one earth. The earth's mass we more than 6 billion people. When we constantly seeking development, please don't forget her resources are limited.
In the city, we can find out the various kinds of pollution. Automobile exhaust air becomes more and more turbid. The river has been unable to direct drinking water. Garbage like mountain. City has become increasingly crowded.
Pollution not only affects people's health, but also destroy the ecological balance.
In the 21st century, we have a responsibility to protect our environment. We are a new mainstream social groups, we have a responsibility to create a harmony between man and nature of the society.