And you'll use each of those smiles at different points in your day and in your life.

你可以用其中的任意一种,在你生活的不同日子，不同情形下。

耶鲁公开课 - 心理学导论课程节选

So when we talk about p orbitals, it's similar to talking about s orbitals, and the difference lies, and now we have a different value for l, so l equals 1 for a p orbital, and we know if we have l equal 1, we can have three different total orbitals that have sub-shell of l equalling 1.

当我们考虑ｐ轨道时，这和ｓ轨道的情形和相似，不同之处在于ｌ的值不一样，对于ｐ轨道，ｌ等于１,我们知道如果ｌ等于１,我们有３个,不同的轨道。

麻省理工公开课 - 化学原理课程节选