抛丸清理是利用星铁与铸件之间的摩擦和轻微撞击来实现清理的。
参考答案：对
handsome（）
A. comfort
B. Europe
C. improve
D. progress
Their sudden attack made us more ________ of the danger around us.
A．familiar
B．particular
C．aware
D．doubtful
