标题: 求助答疑 [打印本页] 作者: sunnychen123 时间: 2011-10-21 14:56 标题: 求助答疑 一道语法题，怎么也看不明白 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[CH1] had spent nearly six hours a week
B.chores; by 1997 that figure had grown to nearly six hours a week
C.chores, whereas nearly six hours a week[CH2] were spent in 1997
D.chores, compared with[CH3] a figure of nearly six hours a week in 1997
E.chores, that figure growing to nearly six hours a week in 1997[CH4]