unlubricated surface

例句：

1. 1.The machine's unlubricated surface is causing the problem.
   机器的未润滑表面导致了这个问题。
2. 2. The new paint job on the car looks like an unlubricated surface.
   汽车上的新油漆看起来就像未润滑的表面。
3. 3.The tool's unlubricated surface made it difficult to grip.
   工具的未润滑表面使得握持变得困难。