朗费罗幽默的秘密源泉并不是欢乐而是悲伤。天堂里没有幽默。

The concept of a black hole firewall challenges our understanding of quantum mechanics and general relativity.

The key to performance is elegance, not battalions of special cases.

诗歌是简洁和强度的艺术。

只要能够改变你自己的头脑，你就可以永远保持年轻。