grind away造句怎么写

A mill is usually used to remove junk in the hole or to grind away all or part of a casing string.

Wang Lao-Er could not grind away and was afraid of his daughter-in-law. His face was as colourful as the moon.

The rover was to use its rock abrasion tool Sunday to grind away at a martian outcropping dubbed "Flat Rock," but the tool left "no discernible impression on the rock," NASA's Jet Propulsion Laboratory reported.