数学不是一项观赏性运动。

电子并非一个简单不可分割的实体，而是一个复杂系统，其行为只能通过量子力学定律来理解。

The fact is that every writer creates his own precursors. His work modifies our conception of the past, as it will modify the future.

Leaders must be willing to take risks if they want to create meaningful change.