There are two worrying features of the slowdown. One is that it has been particularly sharp in the world's most populous countries, India and China.

（经济）放缓有两个令人担忧的特点。其一，在世界上人口最多的国家——印度和中国，这种现象尤为明显。

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China is the world's most populous country with a population of 1.1 billion, which makes up approximately a quarter of the world population.

中国是世界人口最多的国家，有11亿，约占世界总人口的四分之一。

《新英汉大辞典》

As census results from the world's two most populous countries pour in, the China India demographic transition debate rages on.

随着中印这两个全球人口最多的国家公布人口调查结果，两国的人口状况变迁问题得到热议。

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"Such is the demographics of China, " he said, predicting that more than 200 million homes in the world's most populous country will tune in to see Mr. Zou, who, at 31 years of age, is a gray beard in terms of a fighter making his pro debut.

WSJ: 'Fists of Gold' Zou Shiming Boxing Match Fires Up China