And then, if we have time at the end, we'll introduce one last topic, which is isoelectronic atoms and ions.

最后，如果有时间的话，我们将再介绍最后一个主题：,等电子原子与离子。

麻省理工公开课 - 化学原理课程节选

If I have some time, I'll tell you later.

如果待会儿有时间的话,我给你们讲讲这个

耶鲁公开课 - 基础物理课程节选

And although I don't really have the fantasy that many of you will read this stuff twice, if you had the time to do it, that would be a wonderful thing to do.

并且尽管我不会真的认为,你们中的有些人会读两遍这些材料，如果你有时间去读的话，那将会是很棒的事去做。

耶鲁公开课 - 死亡课程节选