====prep-1-7========================================

s2206001

Obtaining aninvestment-grade rating will keep the county's future borrowing costs low,protect its already-tattered image, and increase its ability tobuy bond insurance.

(A) Obtaining an investment-graderating will keep the county's future borrowing costs low, protect

(B) To obtain an investment-graderating will keep the county's future borrowing costs low, and protect

(C) Having obtained aninvestment-grade rating will, in keeping the county's future borrowing costslow, protect

(D) To obtain an investment-graderating would keep the county's future borrowing costs low, protecting

(E) Obtaining an investment-graderating, keeping the county's borrowing costs low, would be protecting

OA: A

并列结构，CDE错；B是不定式做主语，A是doing动名词做主语，二者有何区别？对于后面的并列结构，我觉得应该B的做法没有问题。

s2206001

will do A, and do B, and do C. 这样多个动词并列不会觉得省略了will就意思不明确了。不过你说的逗号这个问题，我觉得很正确！问题可能就是在这里。

此外，我觉得to do做主语不恰当，很少有to do这样做主语的，较多的是To do A is to do B，毕竟to do不是动作。

Antonia1213

C是在feed和corral逻辑意思紧密的时候都可以用and连起来的
而B选项中will keep the county's future borrowing costs low, and protect……
应该是will protect will increase
我觉得问题是出在了逗号上 去掉最后一个逗号 把两句并起来
这是我的理解 我也发帖在问
and就是相当于；的作用

s2206001

举例如下
It is an oversimplified view of cattle raising to say that all one has to do with cattle is leave them alone while they feed themselves, corral them, and to drive them to market when the time is ripe.
(A) all one has to do with cattle is leave them alone while they feed themselves, corral them, and to
(B) all one has to do with cattle is to leave them alone to feed themselves, to corral them, and
(C) all one has to do with cattle is leave them alone while they feed themselves and then corral them and
(D) the only thing that has to be done with cattle is leave them alone while they feed themselves, corral them, and
(E) the only thing that has to be done with cattle is to leave them alone while they feed themselves, to corral them, and

Key is C

Antonia1213

你确定吗？我觉得这个应该是可以接受的吧，好像and除了最后一个不能省略之外，其他都是可以保留也可以省略啊。

-- by 会员 s2206001 (2010/11/20 18:34:29)

请举例~我看到过and连用的情况 在GMAT中
只有X1， X2 AND X3, AND X4  而且X都不是完整句子

s2206001

你确定吗？我觉得这个应该是可以接受的吧，好像and除了最后一个不能省略之外，其他都是可以保留也可以省略啊。

Antonia1213

不定式to obtain是可是做主语的
B主要错的是do1，and do 2，and do 3是不对的
应该是do 1，do 2，and do 3