手动工具选用不正确可导致不必要的（）。
A、意外损失
B、意外发生
C、意外破坏
参考答案：B
I'm sorry that I can not accept your ________ to attend your birthday party, Linda, because I'm
________ to answer all the customers' letters tonight by my boss. [ ]
A. requirement; required
B. demand; requested
C. request; asked
D. request; required
影响芳香酶的抗肿瘤药物是（）。
A．氟尿嘧啶
B．阿糖胞苷
C．来曲唑
D．美法仑
E．卡莫氟
