物流系统能提高效率，但不能增加销售收入，提高企业产品在市场的占有率。( )
参考答案：错
对人员密集场所实施消防监督检查时，尤其要注意检查员工（）在场群众疏散的知识和技能。（易）
A、督促
B、号召
C、跟随
D、组织引导
—I’m afraid you missed a fantastic lecture yesterday. How come you were absent from it?
—If you _______ know, I asked for a day off and visited a relative of mine in hospital.
A．might
B．may
C．shall
D．must
