这句话表达了茅以升对桥梁建设事业的执着追求和不懈奋斗的精神。

"The role of business is to produce goods and services that people value more highly than their cost, and to do so while consuming as few resources as possible."

Pain is temporary. Quitting lasts forever.

"Books are the plane, and the train, and the road. They are the destination, and the journey. They are home."

解释：药物之间有阴阳、子母、兄弟等配对关系，说明药物配伍的原理。