关于润滑车门止动器说法错误的是（）
A.通过润滑可以减少摩擦噪音
B.通过润滑可以减少磨损
C.必须使用专用润滑脂
D.可以使用机油润滑
参考答案：D
The radio set __ _ last week has been out of order.
A．I bought
B．I bought it
C．which I bought it
D．what I bought
