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Natural experiments can provide valuable insights into economic questions.

生命是一朵千瓣蓮花，我拒絕了綻放的同時，我也拒絕了枯萎。

Leadership is about making others better as a result of your presence and making sure that impact lasts in your absence.

If a problem cannot be solved， enlarge it.

如果你沒有得到奇跡，你仍然可以成為別人的奇跡。

組合數(shù)學就像是不用實際計數(shù)的計數(shù)藝術(shù)。