He _____ play football but he can play basketball. [ ]
A. can
B. do
C. don't
D. can't
答案:D
I was sleeping when the telephone rang again.It was the third time that I ________ that night.
A.have been interrupted
B.had been interrupted
C.interrupted
D.had interrupted
对某地交通警察和户籍警察的死亡情况进行回顾性队列研究,得到如下结果:
户籍警察的SMR为()
A.0.2
B.0.18
C.0.44
D.2
E.0.5