Some of was not newly formed obviously, as it's been smoothed out by footprints or dirt, while others were recent, because the soil around the hole was very smooth, very clear outline.

有些孔洞显然不是新近形成的，因为已经被脚印或灰尘抹平了，有些则是最近的，因为空洞周围的泥土很光滑，轮廓很清晰。

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A team of scientists came to this controversial conclusion by dating human footprints preserved by volcanic ash in an abandoned quarry in Mexico.

对保存在火山灰中的人类足迹进行年代测定后，一个科学家小组得出了这一具有争议性的结论。这些火山灰是在墨西哥一个废弃的采石场被发现的。

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In early January 2010, another group of scientists found the oldest fossilized footprints made by a four-legged creature

在波兰东南部的圣十字山的一座废弃的采石场，（科学家）曾发现过动物脚印的化石，经鉴定，为3.95亿年前形成，比发现的最古老的四角龙（一种拥有四肢而非鳍的脊椎动物）化石要早1.8亿年。

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By working towards his degree, McCreery is following the footprints left by some of his country idols.

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If companies adopted work-from-home cultures, would they reduce their carbon footprints by cutting down on employee commuting, de-congesting highways to create space for effective rapid bus transport systems, and reducing need for space and energy-devouring office buildings?

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What we want to do is hone our skills as traders, and understand what setups and footprints left by a stock are signs it is ready to move.

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