天有不测风云，人有旦夕祸福
tiān​yǒu​bù​cè​fēng​yún, rén​yǒu​dàn​xī​huò​fú

unpredictability

天有不测风云，人有旦夕祸福 (天有不測風雲，人有旦夕禍福) tiān​yǒu​bù​cè​fēng​yún, rén​yǒu​dàn​xī​huò​fú
unpredictability
fortune as unpredictable as the weather, every day may bring fortune or calamity; something unexpected may happen at any moment

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