洪灾的危害可以用英语表示为 "flood hazards".
洪灾的来源可能有多种，例如降雨过多、冰雪融化、河流暴涨、山体滑坡、海岸冲刷等。
下面是一些英文例句及其中文翻译：
Flooding caused by heavy rainfall can lead to property damage and loss of pfe. (由大雨造成的洪水会导致财产损失和生命损失。)
The melting of snow and ice can also contribute to flood hazards. (冰雪融化也会导致洪灾。)
River flooding can occur when water levels rise rapidly due to heavy rainfall or a dam failure. (河流暴涨可能是由大雨或坝址垮塌造成的水位迅速上升造成的。)
Landspdes can cause flooding when they block rivers or streams. (山体滑坡会阻塞河流或小溪，导致洪水。)
Coastal flooding can be caused by high tides, storms, and sea level rise. (海岸洪水可能是由高潮、风暴和海平面上升造成的。)