阅读并理解电视广告词"Ifwedon'tsavewater，thelastdropofwaterwillbeatear-drop．"并根据下面提示，写一篇80字左右的短文．要点提示词汇参考益处水的重要性生活离不开水

It's well known that water is very important to man．【高分句型】We can't live without water．（益处）The amount of water which is suitable to drink is falling quickly．【高分句型】But some people don't care about it．They waste a lot of water in their daily life．Even worse，they pour dirty water into rivers．They throw rubbish into rivers，too．Many rivers and lakes seriously polluted（存在问题）．Something must be done to stop the pollution．In this way，We can live happily．If we don't save water，the last drop water will be a teardrop．【高分句型】（建议 ）