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正是在我们最黑暗的时刻,我们必须集中精力看到光明。
物理学的美丽在于它能够用简单的方式解释复杂的事物。
The past is full of voices—we just have to listen.
The challenge of our time is to harness energy without harming the planet.
The success of any political system depends on its ability to generate legitimacy in the eyes of its citizens.