flood retention的用法和樣例：
例句
- Houses built within flood storage and detention areas shall have flat roofs.
在蓄滯洪區內建造房屋應當採用平頂式結構。 - A flood storage and detention area means a depression or a lake from outside embankments including flood--diversion mouths for temporarily storing floodwater.
蓄滯洪區是指包括分洪口在內的河堤背水面以外臨時貯存洪水的低洼地區及湖泊等。
