Backpacks have become common and popular among students in the past 30 years.

在过去的30年里，背包在学生中变得普遍和流行。

youdao

But our genes have certainly not changed in the past 30 years.

在过去30年里，我们的基因没有任何变化。

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The average global temperature has climbed sharply in the past 30 years.

全球平均气温在过去的30年中急剧升高。

youdao

Indeed,volatile food prices, population growth, low agricultural productivity and the potentially devastating effects of climate change make it a particularly daunting challenge. The IFAD president says over the past 30 years, agricultural productivity in developing countries has been stagnant or in decline. He blames it on years of under-investment.

VOA: standard.2010.03.29

During the past 30 years, China maintained a very high growth rate in terms of GDP.

在过去的30年里，中国保持了极高的GDP增长率。

斯坦福公开课 - 百度CEO李彦宏演讲：全球最大搜索引擎的发展课程节选

Thousands have died in Maoist campaigns across central and southern India in the past 30 years.

BBC: NEWS | South Asia | Indian Maoists 'attack village'

In the past 30 years, Aunt Cayita has taught close to 1, 300 women this art craft.

FORBES: Connect

No new treatment has been created for multiple myeloma in the past 30 years.

FORBES: Millennium's On A Roll