It _____ a small house in the past. [ ]
A. was
B. were
C. is
答案:A
促使早产儿动脉导管关闭的药物是()
A.硝苯地平
B.卡托普利
C.前列腺素
D.吲哚美辛
E.双嘧达莫
采用分馆制建立的农村流动书库在经费投入上,全部由总馆承担。