Some people imagine to leave this fearful world, only to come down to earth. Scientists tell us that of all the stars known in the vast universe, the earth is the only planet on which human beings can survive. But now we are facing the risky problems concerning our existence on earth.
Worldwide environmental deterioration (恶化) is alarming. The earth is plagued with population explosion, energy crisis, lack of food, housing problem and environmental pollution. During the process of industrialization, human beings are pursuing crazily the benefits from the economic growth. Now we have suffered from the results. The overuse of natural resources has affected ecosystem(生态系统) on earth.
On the whole, the problem is in the rise. Now we must realize the urgency of the situation. If the situation cannot be under control, we will have no place to live on, let alone for further development. Protect the earth. This is the call of all the peoples who cherish (珍惜) life, nature and a sustainable society. The reason is obvious, we have one lifeboat only the earth.
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