1. According to its proponents, a proposed new style of aircraft could, by skimming along the top of the atmosphere, fly between most points on Earth in under two hours.

2. By skimming along the top of the atmosphere, proponents of a proposed new style of aircraft say it could fly between most points on Earth in under two hours.

3. A proposed new style of aircraft could fly between most points on Earth in under two hours, according to its proponents, with it skimming along the top of the atmosphere.

4. A proposed new style of aircraft, say its proponents, could fly between most points on Earth in under two hours because of its skimming along the top of the atmosphere.

5. According to its proponents, skimming along the top of the atmosphere makes it possible that a proposed new style of aircraft could fly between most points on Earth in under two hours.

XY04-SC-2的问题有4个：如下

1

 in under two hours和in two hours意思相同？？？

2

 a style of +名词，主语是名词还是style?

（A）

According to its proponents, a proposed new style of aircraft could, by skimming along the top of the atmosphere, fly between most points on Earth in under two hours.

记得OG中关于A of B ，AB都有被修饰和被指代的可能；联想到这道题，明显是aircraft作了主语，是AB都可以做主语呢还是只有B可以做主语？

3

在这道题里，如果不考虑逻辑主语的问题，那么with it -ing" is acceptable under GMAT while "prep+one's doing" is wrong.是不是可以当作一个规则呢？？？？？。

C   A proposed new style of aircraft could fly between most points on Earth in under two hours, according to its proponents, with it skimming along the top of the atmosphere.

D  A proposed new style of aircraft, say its proponents, could fly between most points on Earth in under two hours because of its skimming along the top of the atmosphere.

关于with it skimming;    because of its skimming

在白勇的书里with it -ing" is acceptable under GMAT while "prep+one's doing" is wrong.

我在OG里看过prep+one's doing要省略one's，否则错误，

因为看到大家的讨论说

有NN在讨论贴说：不觉得D中的its doing是错的, 至少不是什么硬伤.

4

  有个NN这样解释E，大家记得有这个大全和OG里面都有potential和could/can形成redundance吗，我没有找到。5555。他的解释对吗？？

我认为E的错误在于possible和could形成了redundancy,possible本身就表示了一种可能性，而could也是猜测的语气.

偶记得大全和OG里面都有potential和could/can形成redundance,所以偶觉得possible和could也是同样的道理.

此外,E还有另外一个错误,According to its proponents当中的its指代不明,因为和它要修饰的东东隔太远了,而且中间还有单数的atmosphere干扰.

不知道偶的解释对不对?

in under two hours   --- is ok  here..  all choses have it..

A of B , 主语要看逻辑，

in this case:  aircraft  是主语，  否则。 不合逻辑。

我认为E的错误在于possible和could形成了redundancy,possible本身就表示了一种可能性，而could也是猜测的语气.  同意

3

在这道题里，如果不考虑逻辑主语的问题，那么with it -ing" is acceptable under GMAT while "prep+one's doing" is wrong.是不是可以当作一个规则呢？？？？？。
            

C   A proposed new style of aircraft could fly between most points on Earth in under two hours, according to its proponents, with it skimming along the top of the atmosphere.

D  A proposed new style of aircraft, say its proponents, could fly between most points on Earth in under two hours because of its skimming along the top of the atmosphere.

关于with it skimming;    because of its skimming
            

在白勇的书里with it -ing" is acceptable under GMAT while "prep+one's doing" is wrong.

我在OG里看过prep+one's doing要省略one's，否则错误，
            

因为看到大家的讨论说
            

有NN在讨论贴说：不觉得D中的its doing是错的, 至少不是什么硬伤.

这个还不会，顶一下。

这个还不会，顶一下。

with--型独立结构，与主句形成紧密的逻辑联系，

形式为：with + n. + -ed/-ing; with + n. +adj. with + n. +介词短语--                             see OG 104

With sth doing …with arms and legs hanging...to modify sleeping ,就近修饰            OG 113                                                                                                                                       

so i think "with its doing "  is unidiomatic

同意，

记下来，如果我在看OG的过程中看到相关例子再告诉你。