拆卸防爆电机接线时，应先（）。
A.检查电源
B.切断电源
C.合上电源
D.检查电机
参考答案：B
EXW术语是13种术语中卖方责任最大而买方责任最小的一种。( )
She _____ his number in the phone book to make sure that she had got it right.[ ]
A. looked for
B. looked up
C. looked after
D. looked like
