Old minds are like old horses; you must exercise them if you wish to keep them in working order.
老脑筋就像老马；如果你想保持它们的工作状态，就必须锻炼它们。
穷人的生活故事是用尖锐的笔写在他的身体上的。
Sustainability isn't just a buzzword—it's the foundation of responsible forestry.
The only purpose for which power can be rightfully exercised over any member of a civilized community， against his will， is to prevent harm to others.
素描就是诚实。没有作弊的可能。画得好就是好，不好就是不好。
森林是地球的肺，我们必须给予它们应有的关怀。
Anybody who has been seriously engaged in scientific work of any kind realizes that over the entrance to the gates of the temple of science are written the words: Ye must have faith.