1. He who will not learn when he is young will regret it when he is old. 少壮不努力，老大徒伤悲2.it is harder to conceal ignorance than to acquire knowledge. 掩盖无知要比学到知识更难。3.knowledge comes from experience alone.知识来自实践。4.knowledge is a city to the building of which every human being brought a stone.知识是一座城堡，每个人都应为它增砖添瓦。5.knowledge is a treasure, but practice is the key to it.知识是宝库，而实践是开启宝库的钥匙。6.knowledge is power.知识就是力量。7.knowledge is the food of the soul.知识是心灵的食粮。8.knowledge makes humble, igno
