A teacher must have a healthy body, the skills of a farmer, the mind of a scientist, the interest in art, and the spirit of social reform.

The earth gives us coal; our duty is to give back stewardship.

There is no stress in the world, only people thinking stressful thoughts.

流放不仅仅是一个地理概念；它是一种心态。

创新不在于资源，而在于机智。

Words have power—use them wisely.

We must balance the need for energy today with the imperative of protecting the planet for tomorrow.