Nature abhors a vacuum. 自然界里是没有真空的。
Nature has given us two ears, two eyes, and but one tongue, to the end that we should hear and see more than we speak. 天赋我们两耳，两眼，一张嘴巴，归根到底该多听，多看，少说话。
Nature is the glass reflecting truth. 大自然是反应真理的一面镜子。
Nature teaches us to love our friends but religion our enemies. 自然教我们爱朋友，宗教却教我们爱敌人。
Nature, time, and patience are the three great physicians. 自然，时间和耐心，是三大伟大的医生。
Nature will have its course. 天行其道。
Naughty boys sometimes make good men. 顽皮淘气的男孩子有时成为仁人君子。
Necessity and opportunity may make a coward valiant. 需要和机会可能使懦夫变成勇士。
Necessity (or Need) has (or knows) no law. 需要面前无法律。
Necessity is the mother of invention 穷则变，变则通。
Necessity knows no law. 铤而走险。
Need makes the old wife trot. 人急造反，狗急跳墙。(事急老妪跑。)
Needs must when the devil drives. 情势所迫，只好如此。
Neglect of health is doctor's wealth. 忽视健康，医生财旺。
Never be weary of well doing. 行善莫厌烦。
Never cackle till your egg is laid. 事竟成，才声张。
Never cast dirt into that fountain of which thou hast sometime durnk. 不要过河拆桥。
Never do things by halves. 做事情不要半途而废。
Never embark on what comes after without having mastered what goes before. 如未掌握好已学过的东西，切莫从事更深的学习。