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We are all prisoners of our own minds, and it is only through self-reflection that we can break free.

The coal industry must unswervingly follow the path of safe, efficient, clean, and low-carbon development.

I am always glad to think that my education was, for the most part, informal, and had its roots in the soil.

A proof is a device for convincing someone else that a mathematical statement is true.

藝術(shù)不應(yīng)是反映的鏡子，而應(yīng)是鍛造的鐵錘。