在世界环保日来临前夕，联合国教科文组织就如何保护自然资源问题向全世界中学生征文。请根据提示以“Preserving Natural Resource”(保护自然资源)为题，写一篇英语短文。
要点：
1．随着人口的增长和科技的发展，自然资源月益短缺；
2．自然资源不可再生，许多资源濒临毁灭；
3．水资源越来越缺乏；
4．假如人类继续浪费资源。，不采取有效措施，子孙生存将受到威胁.
Preserving Natural Resources
Thrdugh the changes'in the ways Of making a living in a family over several gen,erations, man has been warned against waste of natural resources and emphasizing the urgent need to preserve these resources.
Ever since man appe
