I once ___ in a junior high school for two years.But I am a teacher in a senior high school now and I ____here for 14 yearsA.worked have workedB.had worked have workedC.have worked have workedD.worked work我想问 once 后面 这种应该接什么时态

I once ___ in a junior high school for two years.But I am a teacher in a senior high school now and I ____here for 14 years
A.worked have worked
B.had worked have worked
C.have worked have worked
D.worked work
我想问 once 后面 这种应该接什么时态