taper of groove

例句：

1. 1.The car's tailpipe is a tapered of groove that helps it to burn fuel more efficiently.
   汽车的排气管是一个缩口，有助于它更有效地燃烧燃料。
2. 2.The machine has a tapered of groove that allows it to move smoothly and quietly.
   这台机器有一个缩口，使它能够平滑且安静地移动。
3. 3. The tool has a tapered of groove that makes it easy to grip and use.
   这个工具有一个缩口，使得握持和使用都变得容易。