当房子被水淹没时，可以使用下列表达方式来表达:
The house was flooded.
房子被淹了。
The house was inundated.
房子被淹没了。
The house was submerged.
房子被淹没了。
这些表达的来源均为英语词汇，"flood" 意为"洪水"，"inundate" 意为"淹没"，"submerge" 意为"淹没"。
下面是一些使用这些表达的例句及其中文翻译：
The heavy rain caused the river to overflow and flood the town.
大雨使河水溢出并淹没了小镇。
The house was completely inundated during the typhoon.
台风期间房子被完全淹没。
The boat was submerged under the water.
船被水淹没了。