1. He is a mathematician.
    他是一个数学家.

2. As a contrast, we may consider a famous story: the discovery by Henri Poincare, the great French mathematician, of a new mathematical method called the Fuchsian functions.
    与之相对的是另一件众人皆知的事情：那就是法国伟大的数学家亨利·庞加莱发现被称为富克斯函数的数学新方法的故事。