So, if you can flip your lecture notes over and just write on the blank space, we're going to cover electronegativity first here, and specifically, you can go back and fill this in to your lecture 9 notes, if you want to stay organized, but I just suggest just writing it on lecture 10 notes now and going back.

因此，请大家把讲义翻到背面,就在空白处做一下笔记，我们要先讲一讲电负性，特别提醒一下，大家可以,回到第九课的讲义并把这些记在那里，如果你想保持条理性的话,但是我建议大家先写在第十课的讲义上,回去再记到第九课的讲义上。

麻省理工公开课 - 化学原理课程节选

So, let's go back to the notes, and let's fill these in, seven electrons. Another way you could have known them was to look at Lewis' notes here, where if look at this box carefully you see there are seven dots around the cube, so there are his seven valence electrons.

那么，让我们回到讲义，把它们填进去，七个电子，还有另外一种方法可以知道这些,那就是看看路易斯的讲义这里，大家可以看到这个立方体周围有七个点,因此有七个价电子。

麻省理工公开课 - 化学原理课程节选