Well, if this thing is going to vibrate for any length of time it better be a standing wave.

好的，如果它在任意时间振动,那它就是驻波。

麻省理工公开课 - 固态化学导论课程节选

All right. So you probably read in the book that the bassoon is a double reed instrument, and so just to show you what that looks like-- You've probably seen it but if you haven't, two pieces of wood vibrate together when I blow through them.

好的,你们可能在书上看到过,巴松管是个双簧乐器,我将为你们演示双簧怎样演奏,你们可能见过,如果没有请看我演示,我吹奏时,两个木片会一起震动

耶鲁公开课 - 聆听音乐课程节选