New equipment and other improvements reduced the amount of time—fromeleven hours in 1982 to six in 1988—needed by workers so that theycould produce a ton of steel. A. needed by workers so that they could produce B. needed when workers are producing C. workers need in producing D. workers needed toproduceD E. workers need for their producing of 答案是D 我选的A 大家都说A有严重的语法错误我怎么看不出来呢 大家都说没有因果关系,我一开始就是觉得应该有因果关系所以选了A排除了D 现在看看是不是如果原句这样说:New equipment and other improvements reduced the amount of time needed by workers so that they could produce a ton of steel (an hour)加上这样一个时间性的词就对了呢? 还有A严重的语法错误在哪啊?? 求教