* * 创伤最易造成的并发症是（）。
A. * * 狭窄
B.尿瘘
C.慢性 * * 周围脓肿
D.尿失禁
E.阳痿或阴茎萎缩
参考答案：A
From the space, the astronaut can see more than 70 percent of the earth _____ by water. [ ]
A. are covered
B. is covered
C. covering
D. cover
正常QRS波群时限为
A．≤0.10s
B．≤0.11s
C．≤0.12s
D．≤0.13s
E．≤0.14s
