He gashed his hand on a sharp piece of rock.

他的手在一块尖石头上划了一个大口子。

《牛津词典》

If you've been lucky enough to look at a piece of rock art close up, you'll know it's an experience that makes you wonder about the passage of time and our own history.

如果你有幸近距离观看一件岩石艺术品，你会知道这是一种让你对时间流逝和历史感到好奇的经历。

youdao

On 6th August, 1996, scientists discovered a piece of rock from Mars, which fell to the Earth 13,000 years ago.

1996年8月6日，科学家们发现了一块来自火星的岩石，它在13000年前落到了地球上。

youdao

The Raptorex Kriegsteini reportedly was discovered inside a single piece of rock in the Inner Mongolia area of China.

VOA: special.2009.10.13

Looking down at a piece of the famous rock, Cari Corrigan suggested its historic importance.

VOA: special.2010.07.28

This piece of basalt rock has been cut with words in the Akkadian language.

VOA: special.2010.06.23

One scientist said it could have been a "random small piece of rock, probably from the asteroid belt".

BBC: Meteor spotted in night sky in England and Wales

Mr Wintringham's wife Marion told the inquest the climb was "very straightforward" and the piece of rock looked "safe".

BBC: Ben Wintringham's abseil death in Morocco an 'accident'

"We are just about to take a piece of rock and, maybe, etch it into the first wheel, " Patrick Chung, a partner at venture-capital firm New Enterprise Associates.

WSJ: For Wearable Computers, Future Looks Blurry