🗣️ 情景例句
Help! Help! I can't swim!
救命！ 救命！ 我不会游泳
Where is the telephone office?
电话局在什么地方？
and we control it by means of the mud which we circulate down the drill pipe.
我们让泥浆顺着钻杆向下循环，用这种方法来控制压力。