Appalachian
n. 阿巴拉契亚山脉\\na. 阿帕拉契山脉的
🗣️ 情景例句
I'll be back
我会回来
Who undertakes many things at once, seldom does anything well.
许多事情同时干，一件事也办不成。
and we have to lower into the ground and haul out of the ground great lengths of drill pipe which are rotated by an engine at the top and are fitted with a cutting bit at the bottom.
我们必须把很长的钻杆一节节地钻入地下，然后再从地下拉出来。钻杆顶部安装的发动机带动钻杆旋转，它的底部装有钻头。