伏尔泰（1694—1778）

Mike had just finished his lunch and was about to take a break _____ an unexpected visitor came.

A．when

B．while

C．so

D．for

下列哪项不属于配送中心的主要功能（）

A.储存功能

B.分拣功能

C.配送功能

D.计划功能

Had it not been for the fact that she_____ in the leg, she might have passed the exam.

A．injures

B．had injured

C．got injured

D．would have got injured

市场调研的目的？

在防止药物制剂氧化过程中，所采取的措施

加入磷酸盐缓冲液______。

A．减少与空气接触
B．避光
C．调节pH
D．抗氧剂
E．金属离子络台剂