在泌尿系统的结构中，具有暂时贮存尿液作用的器官是 [ ]
A．肾脏
B．输尿管
C．膀胱
D． * *
答案：C
四肢瘫痪的病人适合选用（）
A.一般轮椅
B.低靠背轮椅
C.高靠背轮椅
D.电动轮椅
Peter__________be really difficult at times even though he's a nice person in general. [ ]
A. shall
B. should
C. can
D. must
