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激变；剧变；动乱
An upheaval is a big change which causes a lot of trouble, confusion, and worry.
例句
Wherever there is political upheaval, invariably there are refugees...
哪里有政治动乱，哪里就一定有难民。
Having a baby will mean the greatest upheaval in your life.
有了孩子意味着你的生活要发生重大的变化。