1·Helium is the by product of millennia of radioactive decay from the elements thorium and uranium.
氦是钍和铀元素数千年放射性衰变的副产品。
2·For millennia the average person's stance toward providing for himself had been, ultimately I'm on my own.
几千年来，一般人对于养活自己的立场是，最终我要靠自己。
3·Once the soil has been removed by erosion, only the passage of centuries or millennia will enable new soil to form.
一旦土壤被侵蚀，新的土壤只有经过几个世纪或几千年才能形成。
4·We know that over the past millennia the climate has undergone major changes without any significant human intervention.
我们知道，在过去的几千年里，气候在没有任何大型的人为干预之下发生了剧大变化。
5·While it is unknown just how much of this is true, it is certainly known that silk cultivation has existed in China for several millennia.
虽然我们不知道这其中有多少是真实的，但可以肯定的是，丝绸栽培在中国已经存在了几千年。
6·Perhaps even earlier, there had emerged on the steppes of Inner Eurasia the distinctive types of pastoralism that were to dominate the region's history for several millennia.
也许更早的时候，在欧亚大陆内部的大草原上就出现了独特的游牧文化，这种文化主导了该地区几千年的历史。
7·If represented graphically, the curve for all these changes looks rather like that well-known hockey stick: with little change over millennia and a dramatic upswing over the past decades.
如果用图表进行展示的话，这些变化呈现出来的曲线很像大家熟悉的曲棍球杆：以往数千年都没什么变化，而在过去的几十年内却突飞猛涨。
8·In the years since the Pleistocene epoch, native species have adapted to the changing environmental there, plants, smaller animals, they have been evolving without megafauna for millennia.
在更新世以来的这些年里，当地的物种已经适应了那里不断变化的环境，植物，小动物，它们已经在没有巨型动物的情况下进化了几千年。
9·It's been disturbed for the first time in millennia.
这是千年来第一次被打扰。
10·Arching 275 feet and across 290 feet, Rainbow Bridge in the Utah desert has been a source of inspiration and wonderment for millennia.
拱高275英尺，跨度290英尺，犹他州沙漠里的彩虹桥一直是几千年来的灵感和奇迹的来源。