So, if you by chance, I know it's very rare, but if by chance you don't get the class you can always follow up later.

如果你们偶然，我知道不太可能，但是如果不小心你们错过了某节课,你们就可以在之后补回来了。

麻省理工公开课 - 固态化学导论课程节选

I don't know if you realize how rare that is,in a college.

这在大学里很少见。

耶鲁公开课 - 新约课程节选