"Caverns"[img]2012q1/ct_etoefm_etoefspeakc_1513_20121[/img] Now listen t

[Narrator 2] Number 6. Listen to part of a lecture. Then listen for a question about it. After you hear the question, you have 20 seconds to prepare, and 60 seconds to record your answer.
[Narrator 1] Now listen to part of a lecture in a geology class. The professor is discussing caverns.
[Professor]
    Okay, as you’ll recall, caves form in limestone when acidic groundwater follows some kind of weakness in the rocks. Now the rock formations in a cavern... that’s the technical name that we use for a cave... the rock formations there are of two kinds... stalactites and stalagmites. Both of these formations are water that contains dissolved minerals that... that accumulate and build deposits. But stalactites hang down from the ceiling of the cavern, and stalagmites protrude up from the floor of the cavern. Well, these words sound a lot alike, and this can be confusing, so I always tell my students to remember that there is a t in stalactites, and the t has a tail that hangs down just like the stalactites that hang down from the ceiling of the cave, but there is an m in stalagmites and the points on an m stick up like the stalagmites that protrude up from the ground in a cave. And if that doesn’t work for you, another way to remember the difference is that stalactite has a c in it, and so does the word ceiling, whereas stalagmite has a g in it, and so does the word ground. So stalactites drip down from the ceiling and stalagmites build up from the ground. So with these little tricks for remembering the difference, I expect you all to get this right on the next quiz.
[Narrator 1] Using the main points and examples from the lecture, describe the two kinds of rock formations in a cavern, and explain how the professor helps his students remember the difference between the two.
[Narrator 2] Please prepare your answer after the beep.
Beep
[Preparation time: 20 seconds]
[Narrator 2] Please begin speaking after the beep.
Beep
[Recording time: 60 seconds]
Beep