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未來可以通過現(xiàn)在的行動改變。

Meeting energy demand while reducing emissions is the defining challenge of our time.

在每個流亡者的心中，都有一個永遠不會離開的故鄉(xiāng)。

The challenge of quantum computing is not just technical but also conceptual.

The only way to deal with an unfree world is to become so absolutely free that your very existence is an act of rebellion.

任何實驗的價值和效用都取決于材料是否適合其使用的目的。