Aerodrome and Ground Aids的用法和样例：
- The stone was pecked and ground into cylindrical pestles.
- In view of low milling efficiency, the effect of milling form, loading coefficient of materials,rotational speed of ball mill, milling time and grinding aid on milling efficiency was discussed.
- The stone was pecked and ground into square flags.
- You must weld and grind this area before painting.