"Learn as though you would never be able to master it; hold it as though you would be in fear of losing it."
       Confucious (551-479 BC); Chinese philosopher. (来源：英语学习门户网站EnglishCN.com)

 "It is the province of knowledge to speak, and it is the privilege of wisdom to listen".
    Oliver Wendell Holmes, Sr. (1809-94); U.S. writer, physician.