drainage
n. 排水系统；排水，排泄；排出的水，污水
例句
The area has good natural drainage.
这个地区有良好的天然排水系统。
《牛津词典》
The bricks were bedded in sand to improve drainage.
沙里埋入砖块，以改进排水系统。
Hundreds of miles of drainage canals were built in the wetlands.
湿地上修建了数百英里的排水沟渠。
