Some very ancient sediments were no longer recognizable, having been converted to igneous and metamorphic rocks in the course of mountain building.

在造山的过程中，一些非常古老的沉积物已被转化为火成岩和变质岩，已经无法辨认了。

youdao

That's really eye-opening news, since the Appalachian Mountain Range is, of course, thousands of kilometers to the east of the Grand Canyon.

这真是个让人大开眼界的消息，因为阿巴拉契亚山脉当然在大峡谷以东数千公里处。

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youdao

The mountain boasts the steepest vertical drop of any course in the eastern United States.

VOA: standard.2010.02.09

The Ballymoney man will compete in all the races on the Mountain Course in his own privately-run AMA Suzuki outfit.

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In 2009, Donald looked unstoppable in practice, after completing a lap of the Mountain Course in 17 minutes 13.25 seconds to unofficially become the fastest man in TT history.

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The Velodrome cycling track will be converted into VeloPark, which, with the addition of a mountain bike course and road-cycle circuit, will be open for community and club sports.

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