Yang said the cold spell had been "unprecedentedly long". The rain and snow started in many parts of China on January 10 and have lasted for two weeks.

杨说这次的冷空气持续时间“史无前例的长”。雨雪天气从1月10日开始在中国的部分地区已经持续了两周。

youdao

Still, to have a four-quarter interlude between the declining phases of the same recession would be unprecedentedly long, assuming that real GDP declines in the current quarter.

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Or was it a cyclical event that was inevitable after an unprecedentedly long period of almost unbroken prosperity and increasing wealth that led almost everyone to think we had learned to manage the economy so that serious recessions and Depressions could never happen again?

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