[ C or U ] ground near a lake, a river, or the sea that often floods and is always wet沼泽;湿地
At the mouth of the river is a large area of marsh.河口处是一大片沼泽地。
Rain had been falling steadily all day and the ground had become a marsh.雨整天下个不停,地面成了一片泽国。
marshes [ plural ] UK a large area of marsh沼泽地带
At low tide in the estuary, cows graze on the marshes.河口水位低时,牛就在那儿的沼泽地上吃草。