ZCuZn55Mn3Fe1可用于制造()
A.阀件
B.尾轴衬套
C.螺旋桨
D.摇臂衬套
参考答案:C
Playing on a frozen sports field sounds like a lot of fun. Isn't it rather risky, ________?[ ]
A. though
B. also
C. either
D. too
按货物运输条件不同可以将货物分为普通货物和( )。
A.特种货物 B.大型货物C.轻泡货物 D.堆积货物