急 ！ 还有3天考试，1个SC考点怎么都不明白

大全51.According
to surveys by the National Institute on Drug Abuse, about 20 percent of young
adults used cocaine in 1979, doubling those reported in the 1977 survey.

(A) doubling those
reported in the 1977 survey

(B) to double the
number the 1977 survey reported

(C) twice those
the 1977 survey reported

(D) twice as much
as those reported in the 1977 survey（E）those指代不明

(E) twice the
number reported in the 1977 survey

E

GWD-8-Q41:

When
drive-ins were at the height of their popularity in the late 1950’s, some 4,000 existed in the United
States, but today there are less than one-quarter that many.

1. there are less than
        one-quarter that many
2. there are fewer than
        one-quarter as many
3. there are fewer than
        one-quarter of that amount
4. the number is less than
        one-quarter the amount
5. it is less than one-quarter
        of that amount

A、B，句尾many不对

C is the best

D，the number没有指代对象

E，it没有指代对象

Some这里是大约的意思；

我刚才整理了个帖子，不知道对妹妹是否有用。也请妹妹指点。

http://forum.chasedream.com/dispbbs.asp?boardID=23&ID=265802&page=1

20. GWD26-Q20

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

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

C.  
chores,
whereas nearly six hours a week were
        spent 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

可以看看刘振名的ＧＭＡＴ语法改错精解，有这一章，不过我看了之后还是没怎么明白~~

寒自己一个~

20. GWD26-Q20

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

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

我倒是觉得B比较顺眼一点，可是为什么用过去完成时啊？要是有NN进来顺便看一下吧