搜狗输入法繁体版下载:____ different kinds of ferilizers,the workers further improved their technique.

来源:百度文库 编辑:高校问答 时间:2024/05/06 01:32:28
a. Having been produced b.Being produced
C. Having produced D.producing
为什么选c

c吧.因为produce different kinds of ferilizers 的主语是the workers .用现在完成时,是因为它对improved their technique这个结果了产生影响.

A
表示结果 因为是被动关系 所以选A
........................
我是这么认为的

主语与主句一样,并且表示已完成,所以选C