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Children have real understanding only of that which they invent themselves, and each time that we try to teach them something too quickly, we keep them from reinventing it themselves.

Strengthen international cooperation to promote the improvement of technology and management in the coal industry.

化學的樂趣在于看到不可見的東西變得可見。

最終，我們只會后悔沒有抓住的機會。