结构之美在于其逻辑性。

Youth is not a time of life; it is a state of mind; it is not a matter of rosy cheeks, red lips and supple knees; it is a matter of the will, a quality of the imagination, a vigor of the emotions; it is the freshness of the deep springs of life.

Investing in research today prevents crises tomorrow.

真相很少是纯粹的，也从来不是简单的。