In 1981 children in the United States spent an average of slightly less than two and a half hours a week doing household chores; by 1997 they had spent nearly six hours a week. A. chores; by 1997 they had spent nearly six hours a week(they指代不清,排除) B. chores; by 1997 that figure had grown to nearly six hours a week(过去完成时??) C. chores, whereas nearly six hours a week were spent in 1997(逻辑不对,一周6小时,这是一个频率,不能were spent,排除) D. chores, compared with a figure of nearly six hours a week in 1997(主语是children,不能与a figure比较??) E. chores, that figure growing to nearly six hours a week in 1997(growing不对,排除) 偶能确定排除的是ACE,但是B和D好像都有问题,应该如果选择?答案是B,谢谢指教! |