GWD26-Q20的时态请教

JIERONG1019

20. GWD26-Q20

In 1981 children in the United States spent an averageof slightly less than two and a half hours a week doinghousehold chores; by 1997 they had spent nearly six hours a week.

A.chores; by 1997 they had spent nearly six hoursa week

B.chores; by 1997 that figure had grown to nearlysix hours a week

C.chores, whereas nearly six hours a week werespent in 1997

D.chores, compared with a figure of nearly six hours a week in 1997

E.chores, that figure growing to nearly six hours a week in 1997

正确答案是B.我觉得时态有问题,1997在1981之后,为什么1997用过去完成时,而1981用一般过去时啊?想不通,望NN指教

太太傻傻

时态是由时间状语决定的,比较的对象都是现在. 1981年对于现在是过去,所以一般过去时.1997对于现在也是过去,但是因为有by,所以过去完成时

-- by 会员 lonelyorchid (2011/6/15 20:00:44)

赞！

lonelyorchid

时态是由时间状语决定的,比较的对象都是现在. 1981年对于现在是过去,所以一般过去时.1997对于现在也是过去,但是因为有by,所以过去完成时

JIERONG1019

没有人理我,自己顶