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保持虛心才能了解實情，保持冷靜才能判斷行動是否正確

旋律是音樂的本質(zhì)。

Sustainability isn't a choice—it's a responsibility we owe to the next generation.

The most significant threat to liberal democracy today is not from the outside, but from within.

數(shù)學(xué)的美在于它既精確又富有創(chuàng)造性。