"Historically it's one of the most important parts of the period of World War II in France,the roundup - the rafle du Vel dHiv - is a symbol of collaboration between the French police and the German occupying authorities."

VOA: standard.2010.04.10

Remember, all you have to do is fill in the one or two-letter abbreviation for the chemical symbol.

记住，你们只要,用一两个字母的缩写,来代表化学元素就可以了。

麻省理工公开课 - 固态化学导论课程节选

What it does for him is allow him to buy his aunt this symbol of a middle-class American domesticity, and he is a happy participant in this new purchase.

这让他能够给阿姨,买这个美国中产阶级家庭生活的象征物，而他也很高兴能这么做。

耶鲁公开课 - 1945年后的美国小说课程节选

So, the two most elementary ideas you learn are what is the average velocity of an object, as then ordered by the symbol v-bar.

你们学过的两个最基本的概念是,物体的平均速度,用"v拔"表示

耶鲁公开课 - 基础物理课程节选