The value and utility of any experiment are determined by the fitness of the material to the purpose for which it is used.
语言是过去和未来之间的桥梁。
敢于在古人成就面前一争高低,这是有志气;在今人的成绩面前不虚心,这是没有气量。
倘若我们必须在我们为孩子布置的环境里生活一天,我相信那一定会是一个非常痛苦的经历。
The right of a nation to kill a tyrant in case of necessity can never be doubted.