So if you look at the energy diagram, what we see is that the 4 s orbitals are they're just ever so slightly lower in energy than the 3 d orbitals.

如果你看能量图，我们看到的是4s轨道,他们仅仅比3d轨道,能量低一点点。

麻省理工公开课 - 化学原理课程节选

Slightly happy if you lower your levels of expectations, but not in the long term.

降低期望水平会略微快乐些，但从长远来说行不通。

哈佛公开课 - 幸福课课程节选