inside thread

例句：

1. 1.The machine has an inside thread that makes it easy to adjust the screws.
   这台机器有一个内螺纹，使得调整螺丝变得容易。
2. 2. The bolt has a special inside thread that allows it to be tightened without damaging the surrounding material.
   螺栓有一种特殊的内螺纹，使得在不损坏周围材料的情况下可以紧固。
3. 3.The engineer used the inside thread to create a custom fit for the joint.
   工程师使用内螺纹来为接头创建定制的配合。