VOA慢速英语:An Underground World: Carlsbad Caverns National Park

短语讲解：

1. It is silent, except for the quiet voices of guides and visitors.

except for 除…之外; 若不是
例句：Except for a few fine days, the summer has been wet.
除了少数几个晴天外，整个夏季老是下雨。

2. About 400,000 Mexican free-tailed bats come from Mexico every summer to give birth in the big cave.

come from 源自; 来自某处; 出生于
例句：Ambient noise may come from any direction.
外界噪声可以来自任意方向。

3. Since then, parts of Carlsbad Caverns have been used for movie sets, weddings, even meetings of the Carlsbad City Council.

be used for 用来做…
例句：It can be used for devising systems to protect against frost damage.
它可用来设计防止霜害的方法。

4. In one story in his book, he talks about all the work that was done in the area.

talk about 讨论，谈论
例句：He went on to talk about his accident.
他接着谈到了他的意外事故。