风机启动前为何要关闭阀门？

标准地图时选取的标准点（）。

Mr. Fan _____ this watch in 2005,  he _____ it for 6 years. [ ]

A. bought, has had

B. bought, has

C. has bought, has had

D. has bought, had

治疗结膜炎首要的是（）

A.眼药膏涂眼

B.冲洗结膜囊

C.滴眼液滴眼

D.去除病因

社区卫生服务机构属于（）的医疗机构

A、营利性        

B、非营利性     

C、微利性    D、具有行政职能

国家秘密事项的密级和保密期限一经确定，就不能改变。