Food security is the cornerstone of national security.

文学的力量在于它能够让我们在世界上感到不那么孤独。

热爱传统从不会使一个国家变弱，甚至在生死存亡的关键时刻，他会使国家更强大。

The person who tries to live alone will not succeed as a human being. His heart withers if it does not answer another heart. His mind shrinks away if he hears only the echoes of his own thoughts and finds no other inspiration.

使变量可变很容易。控制恒定的持续时间是诀窍。