我们必须在经济增长和环境管理之间取得平衡。

大脑在我们二十多岁时仍在形成，这意味着它更容易接受变化。

The materials I use are witnesses of time.

The elegance of a proof is as important as its correctness.

The time which we have at our disposal every day is elastic; the passions that we feel expand it, those that we inspire contract it.