氧中毒的临床表现有（）
A.头痛
B.恶心
C.烦躁不安
D.面色苍白
E.进行性呼吸困难
参考答案：B, C, D, E
It's Sunday tomorrow. We go to school.[ ]
A. don't have to
B. haven't to
C. not have to
D. had not better
影响子宫复旧不良的因素是（）
A.初产妇
B.授乳
C.胎盘功能不良
D.子宫炎症
E.长时间卧床
