surface indentation

例句：

1. 1. The surface of the metal is smooth and shiny.
   金属的表面光滑且有光泽。
2. 2.The car's paint has a lot of surface indentations from driving on bumpy roads.
   这辆车的油漆因为经常在颠簸的路上行驶，所以有很多凹陷。
3. 3. The engineer carefully measured the surface indentation to ensure it was within acceptable limits.
   工程师仔细测量了表面的凹陷，以确保它符合可接受的范围。