尿结石的形成部位在
A．肾
B．膀胱
C．肾和膀胱
D．肾和输尿管
E．输尿管和膀胱
参考答案：C
---- The reading room ______ from 9a.m. to 5p.m.
---- It’s 4 p.m. now, but the door ______.
A．is open, is closed
B．closes, opens
C．opens, is open
D．is open, close
一般来说，我国股票市场交易日是每个星期的周一到（）
