"It's a horizontal motion of two pieces of the Earth's crust on either side of a vertical crack in the Earth,"

VOA: standard.2010.01.13

So, here's the reading. So, for example today, there is a vision statement, administrative details and I'm going to get a little bit of teaching towards the end. And, if you wanted to, you could crack the book and look at chapter one.

这是阅读材料，例如说，今天，有一个远景说明，行政管理的细节,末尾的时候我会讲一些教学的内容,如果你们想要的话，你可以打开那本书，翻到第一章。

麻省理工公开课 - 固态化学导论课程节选

For example, the hall prove to measure the magnetic field of a crack caring club.

比如，他们准备测量,某个地方的磁场。

麻省理工公开课 - 媒体、教育、市场课程节选

Every once in awhile, the rangers must crack down on reckless pilots of air boats that skim across the swamp, endangering themselves and others and tearing up delicate foliage.

VOA: standard.2010.03.29

That is something that we can stop," President Calderon has repeatedly urged the United States to crack down on arms shipments south of its border, saying 90 percent of weapons in the hands of drug traffickers originate in the U.S.

VOA: standard.2009.04.17