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The art of doing mathematics consists in finding that special case which contains all the germs of generality.

合作是農(nóng)業(yè)發(fā)展的肥料。

人生起落無常，低谷時別放棄。 ?

"A story is a letter that the author writes to himself, to tell himself things that he would be unable to discover otherwise."

我的人生沒有退路，只有前進。