jig boring

例句：

1. 1. The engineerused a jig boring to make theholes perfectly round.
   工程师使用曲柄钻床制作出完美的圆形孔洞。
2. 2. The jig boring was used to remove the oldmetal from the new one.
   曲柄钻床被用来去除旧金属，以便安装新的。
3. 3. The jig boring was used tocreate the shape of the new part.
   曲柄钻床被用来制造新部件的形状。