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A proof is a way to convince yourself and others that something is true.
系外行星的研究是一段充满惊喜和挑战的发现之旅,激励着我们不断前进。
In business, if you're not moving forward, you're falling behind.
The history of mathematics is a testament to the ingenuity and creativity of the human mind.
There are two sides to every question.