值班守库人员因特殊情况需调换班次,必须经单位负责人同意。
参考答案:对
Helen said she would come to my birthday party, but she hasn’t yet.
A.dressed up
B.turned up
C.made up
D.broken up
系统的基本届性不包括( )
A.相关性
B.独立性
C.目的性
D.层次性
E.整体性