跷跷板中间是断开的，就没法翘了。断层是早就存在的。

来源: 猪钢鬃于 2008-05-23 09:00:42 [博客] [旧帖] [给我悄悄话] 本文已被阅读：次

WENXUECITY.COM does not represent or guarantee the truthfulness, accuracy, or reliability of any of communications posted by other users.