在共存曲线上，一共有两个相。

At a coexistence line, then the number of phases equals to two.

youdao

这个城市一共有两个公众体育场。我们可以玩足球、篮球、羽毛球和网球等。

There are two public stadiums in the city where we can play football, basketball, badminton and tennis.

youdao

一共有两个开关分别来控制灯的一半，那么有时候您可以关掉一半的灯光来节能。

There is 2 switches to control half of the light, thus sometime you can turn off part of them to save energy.

youdao

So there's two different orbitals that can have these three quantum numbers, but if we're talking about electrons, we can also talk about m sub s, so if we have two orbitals, how many electrons can we have total?

所以有两个轨道可以有,这三个量子数，但如果我们讲的是电子，我们还要考虑ｍ小标ｓ,如果我们有两个轨道，一共有多少个电子呢？

麻省理工公开课 - 化学原理课程节选