He works in China now ,but he __ in Africa for eight years.(worked/had worked)

问题描述:

He works in China now ,but he __ in Africa for eight years.(worked/had worked)
请问后面括号里面应选哪一个?为什么?

worked
现在不在非洲了,所以用过去式.大学里考试碰到过这种题可是had worked不是过去的过去吗?是的,可以这么理解,这里没有过去的过去,He works in China now是现在时所以选worked