问题
选择题
Mr. Smith works as a government official now, but he ____________ in a middle school for 5 years.
A.has worked
B.worked
C.had worked
D.had been working
答案
答案:B
Mr. Smith works as a government official now, but he ____________ in a middle school for 5 years.
A.has worked
B.worked
C.had worked
D.had been working
答案:B