释义：生前费尽心思追求各种东西，死后却只能留下一双空手。人生的悲欢离合每天都在上演，寿命的长短和命运的通达与否每天都在变化。

The study of mathematics is the indispensable basis for all intellectual and spiritual progress.

Leaders must have the courage to make tough decisions today for a better tomorrow.

"The past is always present in our lives, shaping who we are and how we see the world."

它们难分彼此，交相辉映。