追求数学知识是一场永无止境的冒险,充满了挑战、惊喜和解决不可解问题的满足感。
我们几乎无法避免这样的推论:光是由同一种介质的横向波动组成的,这种介质也是电和磁现象的原因。
The steel industry is a reflection of a nation's economic strength.
The past is not a burden, but a foundation upon which to build.