The primary rules of obligation are those that require or forbid certain actions.

位卑者不怕攀登高山，贫困者勿需点缀虚幻的光环，朝圣者心中自有上帝，引导一路向前。

Innovation in fisheries management is key to balancing economic growth and environmental stewardship.

The Langlands program is a challenge to the boundaries of human knowledge.

Cryptography is about communication in the presence of adversaries.

最大的残忍是我们对他人绝望的随意忽视。