金属材料的可切削性是指：金属接受机械切削加工的（）。
A、变形量
B、强度
C、性能
D、收缩性
参考答案：C
—Now computers _____everywhere.
—I agree with you.I think they are the most useful inventions. [ ]
A. are using
B. use
C. are used
D. will used
谐和侵入体
