Three-dimensional space is defined by x, y, and z axes.

立体空间可用x，y，z描述。

X and Y position, but move along the Z axis.

X 和 Y 位置，但沿 Z 移动。

You'll sometimes see another one, k, which represents the z axis.

有时你会看到另一个， k，代表 z 。

What about in three dimensions? Well, you add a 3rd axis called the Z axis, which is perpendicular to both the x and y axes.

三维空间中呢 你添加了第三个 叫做Z 它与x和y都垂直。

Or rather, I should say p orbitals, because we're talking about 3 dimensional space here, so there can be one on the x axis, and one on the y axis, and one on the z axis.

或者更确切地说， 我应该说 p 轨道，因为我们这里谈论的是 3 维空间， 所以可以有一个 x ，一个 y ， 一个 z 。

It's like how in solving a Rubik's cube, order matters a lot, Or how rotating a cube about the z axis and then about the x axis gives a different final state from rotating it about the x axis, then about the z axis.

就像解魔方时，顺序很重要， 或者先绕 z 旋转立方体， 然后再绕 x 旋转立方体， 与先绕 x 旋转，然后再绕 z 旋转立方体会产生不同的最终状态。