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過去無法改變，但未來可以。

對沖低油價的最佳方法是降低盈虧平衡成本。

The important thing in science is not so much to obtain new facts as to discover new ways of thinking about them.

"In observational studies, we often have to rely on assumptions that are not directly testable."

The heart is a lonely hunter.

"The past is always with us, for it feeds the present."