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The easiest and noblest way is not to be crushing others，but to be improving yourselves.

Don't be afraid to take risks and try new things.

模形式的算術是理解數論更深層次結構的關鍵。

Reflect upon your present blessings, of which every man has plenty; not on your past misfortunes, of which all men have some.

經濟模型的價值在于其解釋和預測的能力。