As a necessary element of animal, fluorine has very important function in production.

氟作为动物体中一种必需的微量元素，在生产上有很重要的作用。

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As a necessary element of animal, fluorine has very important function in production.

氟作为动物体中一种必需的微量元素，在生产上有很重要的作用。

youdao