Quartz is quartz—a silicon ion surrounded by four oxygen ions—there's no difference at all between two-million-year-old Pleistocene quartz and Cambrian quartz created over 500 million years ago.

石英是石英——由四个氧离子围绕的硅离子——200万年前的更新世石英和5亿年前的寒武纪石英之间没有任何区别。

youdao

He came across the jawbone of a 4.5 million-year-old marsupial.

他偶然发现了一个450万年前的有袋动物的颌骨。

《柯林斯英汉双解大词典》

One interpretation regarding the absence of fossils during this important 100-million-year period is that early animals were soft-bodied and simply did not fossilize.

关于在这一亿年的重要时期中没有化石，有一种解释是，早期的动物是软体动物，根本不会变成化石。

youdao

The small,two-legged creature lived about one hundred-fifty million year ago.

VOA: special.2010.03.16

Because it has been said that each American soilder cost us one million dollars a year Ambassodor is so much cheaper.

有人说一个美国士兵每年要花费一百万美元,相比之下，大使是如此廉价。

普林斯顿公开课 - 国际座谈会课程节选

Aluminum is 25 million tons per year for the whole planet.

铝的产量为每年2500万吨,全世界。

麻省理工公开课 - 固态化学导论课程节选

We estimate Apple will sell 37 million iPads this year and 55 million next year.

FORBES: Amazon Could Fight iPad With H-P Touchpad Pricing Strategy

His current forecast is for iPad unit sales of 32 million this year, and 55 million next year.

FORBES: Apple: iPad Margins Could Be Better Than Street Expects

Car sales in Europe have fallen from around 18.5 million a year before the downturn to an expected 14 million this year.

BBC: Unemployment set to keep on rising, says forecaster