磁粉探伤不能检测奥氏体不锈钢材料，也不能检测（）等非磁性材料。
参考答案：铜、铝
-Have you heard of a person in Qingdao who won a million in the lottery( * * )?
-A million! ______we had won it. [ ]
A. What if
B. Only if
C. What about
D. If only
