郭德纲的相声里解释的最清楚，拇指竖着和放平都有说道

来源: myquestion 于 2020-03-06 05:34:28 [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.