过去时和完成时问题Before he retired ,he was the head of the factory.与before he retired ,he had been the head of the factory.哪个正确?如都正确,有什么区别?

过去时和完成时问题Before he retired ,he was the head of the factory.与before he retired ,he had been the head of the factory.哪个正确?如都正确,有什么区别? 英语时态问题,过去进行-和完成时.有什么区别 例如He was aways working-He had aways worded 过去时和过去完成时问题Before he retired ,he was the head of the factory.与before he retired ,he had been the head of the factory.哪个正确?如都正确,有什么区别? he was very ill before he died为什么he was very ill先完成的动作不用过去完成时,用过去时? 英语时态问题,过去进行-和完成时. 有什么区别 例如He was always working-He had always worked含义有什么不同 过去时和完成时~ 关于过去完成进行时He had been working here for years before he got this job.这是一个过去完成进行时的句子.我不知道下边这个句子能不能这样说：He used to work here for years before he got this job.如果可以,这 before是不是一定和完成时连用? 过去进行时和过去完成进行时的区别? 过去时和完成时的区别 关于过去时和完成时的区别He (gazed at) the display for several minutes before re-entering his shop.括号内的为什么不能用 have gazed at.后面有before 说明 gazed at在re-entering 之前发生 这种情况（包括after）到底 two days before表示句子是完成时还是过去时?为什么? 什么是现在完成进行时和过去完成进行时 过去将来完成时 过去时或完成时～ 过去时或完成时 he hesitated for a moment before kicking the ball,otherwise he would have scored a 请为我翻译一下,还有后面为什么用过去将来完成上时?ordinary,common,usual,normal有什么区别? He couldn't understand spoke English before he moved to Canada.为什么speak和move用过去时?一句话中不是只有谓语动词表现时态就可以了么?为什么speak和move都要用过去时?