He believes that as far back as 30,000 B.C., hunters may have used a system of notation, engraved on bone and stone, to mark phases of the Moon.

他认为，远在公元前30,000年以前，猎人可能会用一套刻在骨头和石头上的符号系统来标记月相。

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Blue flags define the excavation perimeter, while yellow ones mark the location of fossils or stone tools.

蓝旗用来显示发掘地的周长，而黄旗用来标明发掘出化石或石制工具的地点。

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Ancient cultures often modified natural rock formations or built stone monuments to mark the motions of the sun and moon, charting the seasons, creating calendars and monitoring eclipses.

原始文明经常用改造天然石群或修建石碑来记录太阳和月亮的运行和季节变化，创立历法和观测日食月食。

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Lily - not her real name - was in a two-year relationship with "Mark Stone" until 2005.

BBC: Undercover police 'betrayed' women in relationships

But three women suing the Met say they had a long-term intimate relationship with him, as he posed as protester "Mark Stone".

BBC: Undercover police 'betrayed' women in relationships

The glistening arc of water overruns the waiting cup, misses its mark, splashes over table and chair-the pitcher slipping from defeated fingers, striking the stone floor, shattering into jagged shards.

NPR: Excerpt: 'Woodsburner'