1. When it has been decided where we are going to drill, we put up at the surface an oil derrick.
    当钻孔地点决定后, 我们就在那块地面上坚起一个井架.

2. When it has been decided where we are going to drill, we put up at the surface an oil derrick.
    当确定钻孔地点后，我们就在那里竖起一个井架。

3. When a student recently saw two workmen using a pneumatic drill outside his university,
    最近有个学生看见两个工人在学校门外用风钻干活，

4. The geologist needs to know what rocks the drill has reached, so every so often a sample is obtained with a coring bit.
    地质学家需要知道钻头已达到什么样的岩层了, 所以时时要用取钻芯头那样.

5. The geologist needs to know what rocks the drill has reached, so every so often a sample is obtained with a coring bit.
    地质学家需要知道钻头已以到达什么样的岩层，因此时常要用芯钻头取样。

6. This pressure must be under control, and we control it by means of the mud which we circulate down the drill pipe.
    这种压力必须加以控制，我们让泥桨顺着钻杆向下循环，用这种方法来控制压力。

7. 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。

8. As the diamond tip of the drill revolves, it is lubricated by mud.
    在钻机的金刚钻头旋转的时候，泥浆便进行了润滑。

9. As the men refused to stop working, the police attempted to seize the pneumatic drill.
    由于工人拒绝停下手中的活，警察想夺风钻。

10. She did lots of drill in listening.
    她在听力方面受过许多训练。