现在腾讯QQ是网上最流行的网上聊天软件，我的许多同学都在用QQ，几乎每个同学都有QQ号。

Nowadays tencent QQ online is the most popular online chat software, many of my classmates were using QQ, almost all my classmates have QQ number.

youdao

And the reason is, and this will come up on the problems and a lot of students end up using this equation, which is why I want to head it off and mention it ahead of time, we can't use an equation because this equation is very specific for light.

原因是，很多同学在解题时,都会用这个方程，所以我要,事先提醒你们一下,我们不能用这个方程，因为它只对光是用。

麻省理工公开课 - 化学原理课程节选

We're going to really get into this next class, but I just want to introduce it to you to give us a start, and many of you have used Lewis structures in high school, but we'll be doing some much more challenging Lewis structures, I can assure you, in this class here.

其实我们下节课才会详细介绍它，但是今天我只想以简单介绍作为开始，大部分同学在高中就用过路易斯结构了，但是我们会遇到一些更具挑战性的,路易斯结构，我可以向大家保证，在这门课中会的。

麻省理工公开课 - 化学原理课程节选