There are two kinds of gun drills, namely, the center-cut gun drill used for drilling blind holes and the trepanning drill.
深孔钻有两种类型，即用于钻盲孔的中心切削深孔钻和套孔钻。
2
The agriculture sector must be placed at the center of development to cut in half extreme poverty and hunger by 2015.
必须把农业部门放在发展的中心，才能在2015年把极度贫困和饥饿人口减少一半。
3
We cut out holes in the center of larger trees, to make little huts, and built a large one out of large branches and twigs, upon a tree that had fallen down and was resting on another.