What's the world's largest city?
世界最大城市是哪兒？

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獲得171k的回答@Wenzhe Chen：

As of 2015 the World Bank announced in a report on urbanisation the formation of a new world’s biggest city, in terms of population. It is a contiguous city made up of 4 major conjoined cities that have physically merged into one another - as in one can walk on an urban pavement from one to another surrounded by buildings. This is the Pearl River Metropolis in southern China that has now overtaken Tokyo, centred on Guangzhou, but taking in the megacity of Shenzhen, and the smaller cities of Dongguan and Jiangmen also. All in all it boasts of a contiguous urban population of 41 million, with a metro population of 55 million. It is over the border from Hong Kong but doesn’t count it.
2015年世界銀行在一篇關于新世界最大城市形成的城市化報告中指出，就人口而言，這個聯(lián)合城市由4個主要城市相連而成，它們在地理上相互交匯——因為你在城市的人行道上就能從一個城市走進另一個高樓林立的城市，這就是中國南方的珠三角城市圈，現在已經超越了東京。這里以廣州為中心，同時包括大城市深圳，還有較小城市東莞和江門?？傊@個城市圈自詡有4100萬固定人口，城市總人口達5500萬。這個城市圈已經延伸到了香港，但不包括香港。

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獲得992好評的回答@Anurag Jangde：

Tokyo is about twice the population of NYC. If you go back about twenty-five years, NYC was the second-largest city (after Tokyo), but now (2017) it is only ranked around 9th. This is based on metro area.
東京人口約為紐約市的2倍。如果回到約25年前，紐約市是第二大城市（僅次于東京），但現在（2017年）僅排在第九位，這是基于繁華程度劃分的。

If you are speaking of population within the city proper, Shanghai comes in first and NYC drops to 23rd.
如果說的是城市人口的話，上海排第一，紐約要降到23位了。

HOWEVER, NYC was the world’s largest city in the period from about 1925 until the 1950’s. This may be what you're inquiring about.
然而紐約市從1925年到20世紀50年代一直是世界最大城市，這可能是你想知道的。

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獲得945 好評的回答@Tong Zou：

The answers seem to fluctuate on this question a lot and part of it is the definition of a city’s population. If a city is defined by city proper then the most populated city in the world is Shanghai.
這個問題似乎有很多答案，其中有一部分是根據城市人口定義的。如果根據城市規(guī)模劃分，那世界上聚居程度最高的城市是上海。

List of cities proper by population – Wikipedia(Cities like Beijing, Tokyo, Mumbai, Karachi, Chongqing, New York etc all fall below Shanghai’s 24 million)
按人口劃分城市規(guī)模的話，來自維基百科的數據是北京、東京、孟買、卡拉奇、重慶、紐約等都沒有上海的2400萬人口多。

If you define city by its metro area then its Tokyo with 37 million people in the metro area.
如果根據都市區(qū)劃分的話，那東京的市區(qū)有3700萬人口。

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（翻譯：菲菲）