Now let me explain why vibrational theory has some sort of interest in it.  现在我来解释为什么震动理论有一定的道理。

　　These molecules, as you saw in the beginning, the building blocks had springs connecting them to each other.  这些分子正如你们开始时看到的是基本组成，它们之间有弹簧连接着。

　　In fact, molecules are able to vibrate at a set of frequencies which are very specific for each molecule and for the bonds connecting them. 事实上，分子可以在一定的频率下震动，每一个不同的分子和不同的连接方式都有特定的频率。

　　So this is the sound of the O-H stretch, translated into the audible range.  所以这是O-H键发出的声音，转化成人耳可以听到的频率。

　　S-H, quite a different frequency.  S-H键，有十分不同的频率。

　　Now, this is kind of interesting, because it tells you that you should be looking for a particular fact,  现在看来这十分有趣，因为它告诉你，你应该寻找一个独特的事实，

　　which is this: nothing in the world smells like rotten eggs except S-H, OK? 事实是：除了S-H以外，没有其他东西闻起来像臭鸡蛋。

　　Now, Fact B: nothing in the world has that frequency except S-H.  第二个事实就是：除了S-H，没有其他东西有那样的频率。

　　If you look on this, imagine a piano keyboard.  如果你看到这些，想象一下钢琴的键盘。

　　The S-H stretch is in the middle of a part of the keyboard that has been, so to speak, damaged,  S-H键是在键盘的中间部分，可以说键盘的那部分损坏了，

　　and there are no neighboring notes, nothing is close to it.  也没有其他的音符挨着它。

　　You have a unique smell, a unique vibration. 你得到的是一个独特的味道，一种独特的震动。