Having set the optimum population number for planet earth, the World Planners have also set a date by which to achieve their optimum population number.

为地球设定了最佳人口数目，该世界计划者们还设定了一个在该时间之前实现其最佳人口数目的日期。

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The number of juveniles in the general population has fallen by a fifth in the past 10 years.

在过去的10年中，青少年在总人口中所占的比重下降了1/5。

《柯林斯英汉双解大词典》

Since the 1990s, population experts have predicted the number would grow to nine billion before it begins to slow down and possibly decrease.

自20世纪90年代以来，人口专家预测人口数量将增长到90亿，然后增长放慢，甚至可能减少。

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The number of Washingtonians grew about three percent during that period while the United States population increased more than seven percent.

VOA: special.2009.03.20

So, I already said what the number of square miles that were increased, but it increases from six to sixteen million of the population.

我已经提过了领土扩大的面积有多少,而人口从六百万增加到一千六百万

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I want to have the population at a number no greater than 20.

我希望人数是,不要超过20人。

麻省理工公开课 - 固态化学导论课程节选

Well, now my friends, 40-plus years later, we have more than doubled that population number to 6.8 billion.

CNN: 'The Science Guy' says: 'Save the Earth'

But across the population the number of children born with disorders is likely to increase if this theory holds true.

BBC: Older dads linked to rise in genetic disorder

Although the mortality rate is predicted to continue declining, due to a growing and ageing population the number of deaths is expected to rise to about 182, 000 deaths by 2025.

BBC: 13,000 cancer deaths 'can be prevented'