下列不是研磨润滑剂的是（）
A、煤油
B、汽油
C、变压器油
D、甲基硅油
参考答案：D
A transistor radio is sometimes very small. It is very easy to carry…_______, radio broadcasts are better for blind people.
A．Besides
B．However
C．Yet
D．Sometimes
医生用什么药使运动员很快消除疼痛呢？（）
A.氯乙烷
B.二氯乙烷
C.三氯乙烷
D.四氯乙烷
