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尋找互反律是數學史上的一個基本主題。

Choose a life of action，not one of ostentation.

Trust is the most valuable resource in mining—harder to earn than any mineral.

我不創造，我發現。

能源的未來在于平衡當今的需求與未來的責任。

Quality is the lifeline of the enterprise. We always adhere to high standards and strict requirements to ensure that every piece of stone can stand the test of time.