法律是通过社会机构执行的规则系统，用以管理行为。
Crime fiction is the perfect vehicle for exploring the darker side of human nature.
The challenge of modern physics is not just to understand the universe, but to understand our place within it.
The profession of book writing makes horse racing seem like a solid, stable business.
数学不是一项观赏性运动。你必须参与其中。
数学中的每个问题都有解答，关键在于找到正确的路径。