__ you don't hurry up, you'll miss the train. [ ]
A. Until
B. Before
C. If
答案：C
课间休息的时间是10分钟．______．
肛管直肠周围脓肿常继发于（）
A.肛裂
B.肛瘘
C.肛窦炎
D.内痔注射
E.直肠息肉
