优化科技创新资源配置需要在政府的主导下，充分发挥（）的主体作用。
A.政府
B.科研院所
C.高等院校
D.企业
参考答案：D
He has _ for ten years. Ten years __________ a long time to him. [ ]
A.left home; are
B. left home; is
C. been away from home; is
D. been away from home; are
霍乱病原学检查包括（）
A.粪涂片染色
B.粪悬滴镜检
C.制动试验
D.核酸检测
E.增菌培养
