Goaf
n. 废矿
🗣️ 情景例句
This job is killing me.
这活儿都快把我累死了。
What did the doctor say?
医生说了什么吗？
a trough (the lowest point), a height (the vertical distance from the trough to the crest),
波谷（最低点）、浪高（从波谷到浪峰的垂直距离）