阿伦磷酸钠属于（）
A.第一代双膦酸盐类
B.第二代双膦酸盐类
C.第三代双膦酸盐类
D.第四代双膦酸盐类
E.无机磷酸盐类
参考答案：C
— He didn't feel a bit nervous when ______.
— No. He'd had a lot of time ______ for it after all. [ ]
A. interviewing; to prepare
B. interviewed; to prepare
C. interviewing; preparing
D. being interviewed; preparing
设备责任事故
