If I rest, I rust
如果休息，我就生锈

The significant inscription found on an old key — “If I rest, I rust” — would be an excellent motto for those who are afflicted with the slightest bit of idleness. Even the most industrious person might adopt it with advantage to serve as a reminder that, if one allows his faculties to rest, like the iron in the unused key, they will soon show signs of rust and, ultimately, cannot do the work required of them.
一把旧钥匙上刻着一则意味深远的铭文——如果我休息，我就会生锈。对于那些为懒散而苦恼的人来说，这将是至理名言。甚至最勤勉的人也可以此为警示：如果一个人有才而不用，就像废弃的金属钥匙一样，这些才能很快就会生锈，并最终无法完成安排给自己的工作。

Those who would attain the heights reached and kept by great men must keep their faculties polished by constant use, so that they may unlock the doors of knowledge, the gate that guard the entrances to the professions, to science, art, literature, agriculture — every department of human endeavor.
有些人想取得伟人所获得并保持的成就，就必须不断运用自身的才能，以便开启知识的大门，即那些通过人类努力而企及的各个领域的大门，这些领域包括科学、艺术、文学和农业等方面的各种职业。

Industry keeps bright the key that opens the treasury of achievement. If Hugh Miller, after toiling all day in a quarry, had devoted his evenings to rest and recreation, he would never have become a famous geologist. The celebrated mathematician, Edmund Stone, would never have published a mathematical dictionary, never have found the key to science of mathematics, if he had given his spare moments to idleness. Had the little Scotch lad, Ferguson, allowed the busy brain to go to sleep while he tended sheep on the hillside instead of calculating the position of the stars by a string of beads, he would never have become a famous astronomer.
勤奋使开启成功宝库的钥匙保持光亮。休·米勒如果在采石厂劳作一天后，将晚上的时光用来休息消遣的话，他永远不会成为名垂青史的地质学家。著名数学家爱德蒙·斯通如果闲暇时无所事事，永远不会出版数学词典，也不会发现开启数学之门的钥匙。如果苏格兰青年弗格森在山坡上放羊时，让自己那思维活跃的大脑处于休息状态，而不是借助一串珠子计算天上星星的位置，他永远不会成为著名的天文学家。