A good example of that is CH4, because the CH bond is polar but symmetrically disposed in space.

甲烷就是一个很好的例子，因为极性键是,空间对称的。

麻省理工公开课 - 固态化学导论课程节选

And, I know I need to come up with four symmetric equi-length bonds, and let's just see, let's draw the structure here.

我想我们需要,4个对称的等长的键，让我们画出CH4的结构。

麻省理工公开课 - 固态化学导论课程节选

And I picked looking at methane so we could see if there are other factors that we're not considering, that we need to maybe tweak our model a little bit, and I think we'll find that we do if we take a look at a polyatomic molecule, methane, CH4 so c h 4.

我选择甲烷这个例子，我们可以看到,如果有一些我们没有考虑到的因素，我们需要修改一下我们的模型，我们看一看,甲烷CH4这个多原子分子，就会知道这一点，甲烷。

麻省理工公开课 - 化学原理课程节选

CH4 is sp3 carbon hybridization.

能容纳4个原子成键。

麻省理工公开课 - 固态化学导论课程节选