Unfortunately, the general population fails to see that sharks are a vital component of our oceans because they maintain balance in our underwater ecosystem and, now they are facing extinction.

很不幸地，一般民众却不了解鲨鱼是海洋中必需的生物，因为鲨鱼能维持水中生态系统的平衡，不过，牠们现在却面临绝种的命运。

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Sick or dying coral affects the entire ecosystem of this special underwater area.

VOA: special.2009.04.22