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being covered with water (i.e. in a flood); being submerged; being inundated; flooding
大雨で道路が冠水して通行止めになった。
The road was flooded by heavy rain and closed to traffic.
冠水した住宅の復旧作業が始まった。
Restoration work on flooded houses began.
低地が冠水する恐れがあると警告された。
A warning was issued that low-lying areas may flood.