我们的教学方法只有一个，就是必须维持孩子们的高度兴趣和强烈持续的注意力。

The true spirit of delight, the exaltation, the sense of being more than Man, which is the touchstone of the highest excellence, is to be found in mathematics as surely as in poetry.

Innovation in natural gas extraction is key to meeting the world's growing energy demands while reducing environmental impact.