It is the site of what used to be his son's home before Israeli forces came here early one morning this week and demolished it.

VOA: standard.2009.04.09

There it is. He used the prism spectrograph to analyze his results. So what do we have here?

在这里，他用了棱镜分光图来分析他的结果,得到些什么呢？

麻省理工公开课 - 固态化学导论课程节选

And what it's used is to convert one type of group, what's called a carboxylic acid into another type of very reactive intermediate, which is called an acid chloride.

它被用来将一类被称作羧酸的化合物，转化成另外一类活性很高的反应中间体,也就是酰氯。

麻省理工公开课 - 化学原理课程节选

Okay. So again, let's talk about what food used to be and what it is now.

好的,我们将要,再次谈到食品的过去和现在

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What is it about the fact that we don't have something that we used to that makes it worse than ? not having something that we're going to?

要怎么看待,我失去了曾经拥有的事物,要比无法拥有,我们可能拥有的事物更糟糕？

耶鲁公开课 - 死亡课程节选