A down - hole autotracking well pumping unit different from the conventional pumping unit was designed.针对抽油技术的现状和存在的问题,设计了一种不同于有杆抽油方法的井下自动跟踪式抽油装置.It is autumn and they are pumping water out of the swimming pool.入秋了, 他们正在...
There is a pumping station on the edge of the lake.湖边有座扬水站.He was pumping away.他正用抽水机抽水.Aerobic exercise gets the heart pumping and helps you to burn up the fat.有氧运动加速心脏跳动，有助于消耗更多脂肪。...
Droughts and accentuation of soil erosion cause havoc in such areas , making their rehabilitation extremely difficult.旱灾和严重的土壤侵蚀造成巨大的破坏, 恢复起来极为困难.This concentration of airborne firepower wrought havoc with the enemy forc...
There are four major disciplines in earth sciences, namely geography, geology, geophysics and geodesy.地球学又分为四大类, 即地理学, 地质学, 地球物理学和测地学.Why to always syare blankly ineffably , feel sadness namely next.为什么总是莫名的发呆,然后就是感到悲伤.O...