Underdrain
n. 阴沟, 地下沟道, 盲沟, 暗渠
🗣️ 情景例句
Thanks, Ellen.
谢谢 Ellen。
We can live without our friends, but not without our neighbours.
生活可无友，邻居不能无。
What you said was quite true.
你所说的完全符合事实。