Another one, a kind of popular one, is the iceberg idea, that we only see the tip of the iceberg but underneath is where most of the iceberg is hidden.
另一种，也是很普遍的一个，就是冰山模式。 我们只能看到水面上的冰山尖，但是水面下 才是隐藏着的大部分的冰山。