嗯．过去的解剖书上都是这么写的．现在的理解是：

来源: 于 2014-07-16 19:07:34 [博客] [旧帖] [给我悄悄话] 本文已被阅读：次

Hold out your hand and make a fist. If you're a kid, your heart is about the same size as your fist, and if you're an adult, it's about the same size as two fists.

Amazing Heart Facts - PBS