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The solution of a problem appears suddenly and is not approached by a gradual, step-by-step procedure.

林業(yè)的未來在于技術(shù)，但它必須服務(wù)于自然，而不是剝削自然。

In mathematics, the journey is just as important as the destination.

"In mathematics, you don't understand things. You just get used to them."

種樹的最佳時間是25年前，第二好的時間是今天。