Heard melodies are sweet, but those unheard are sweeter.
出自先秦《荀子·哀公》。鸟被逼得走投无路之时就会用嘴啄人,兽到困窘之时就会用爪抓人,人到穷困潦倒之时就会设计骗人。以鸟兽困窘之时的行为为喻,说明人到穷困潦倒之时便会放弃道德操守的原因。
在化学中,就像在生活中一样,有时你需要退后一步才能看到更大的图景。
The world needs all forms of energy to meet growing demand, and natural gas is a cleaner alternative that can help bridge the gap.