Underdense
欠密的
🗣️ 情景例句
If it's a good job,
假如它是个好工作
I'm under a lot of pressure.
我压力很大。
An ocean wave passing through deep water causes a particle on the surface to move in a roughly circular orbit,
穿过深水的海浪使水面上的一个微粒按照一种近乎圆形的轨道移动，