回复：人做任何事都是需要动力的。比如说有人自愿打扫房间，因为他需要一个干净的生活环境，

来源: 于 2013-09-17 11:52:19 [博客] [旧帖] [给我悄悄话] 本文已被阅读：次

even in college, when reading became assignments, we lost interest, but for the books we picked ourselves, could not put the book down, read till midnight :)