图书馆管理主体有（）。
A.政府主管部门
B.图书馆
C.读者个人
D.图书馆内的安全管理部门
参考答案：A, B, D
---- Could you play ________ basketball when you were a primary school student?
---- No, I couldn't, but I could play ________ violin.
A．the; an
B．/; the
C．a, an
D．the; /
某同学在实验室用CO与Fe2O3反应制取5．6g的Fe，实际消耗的CO的质量是 [ ]
A．=4.2g
B．>4.2 g
C．<4.2 g
D．无法确定
