这是美国这边小学生就能搞清的问题了，以Venn diagram 来描述，类，子类，元素之间的关系。

来源: QualityWithoutName 于 2023-01-06 17:10:31 [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.