OG-23 Page568 explanation

OG. No.23  age568 explanation

自由的疑惑：”choice B indicates that between the cities to be served by the plan there is substantial air travel to which ground transportation would represent an alternative. Therefore,, B is the best answer.”  这句话自由没有很明白它的意思，特别是这句话的复杂的预防结构，谢谢大家帮助。

自由的疑惑2：对于D，OG这样解释到：” and D by indicating that such an alternative is not by itself a solution to airport congestion. “ 自由结合了D这个选项，不是很明白含义，谢谢大家指教。

自由的疑惑三：which of the follwong , if true, could proponents of the plan above most appropriatedly cite as a piece of evidence for the soundness of their plan?  自由不是很明白这个问题的语法结构，这个问题属于“支持类的推断题问法”。请大家帮忙分析一下它的语法结构，谢谢大家。

题目如下：

A cost-effective solution to the problem of airport congestion is to provide high-speed ground transportation between major cities lying 200 to 500 miles apart. The successful implementation of this plan would cost far less than expanding existing airports and would also reduce the number of airplanes clogging both airports and airways.

Which of the following, if true, could proponents of the plan above most appropriately cite as a piece of evidence ofr the soundness of their plan?

A)     An effective high-speed ground-transportation system would require major repairs to many highways and mass-transit improvements.

D) many new airports are being built in areas that are presently served by high-speed ground-transportation systems.

What is "预防结构"?

choice B indicates that between the cities to be served by the plan there is substantial air travel to which ground transportation would represent an alternative. Therefore,, B is the best answer

Just rephrase the sentence: There is substantial air travel between the cities to be served by the plan. The gound transaportation would represent an alternative to such air travel.

The key is to break down the sentence and know which part is for which.

D is not as good because it does not offer a direct linkage between ground transportation and air traffic as the correct answer.

刚好正在开始看OG, 试着回答你的问题:

Q1: 转换一下句子结构:

there is substantial air travel (to which ground transportation would represent an alternative) between the cities to be served by the plan.

换言之, 有一个替换方案(ground transportation).

Q2.  and D (by indicating) that such an alternative is not (by itself) a solution to airport congestion.

基本上这句是个独立主格用以详尽描述(D)选项, 大意是(D)改变了premise, 而使得ground transportation变成连接many new airports, 而不是原先的the goal of alternative

Q3.

试着还原一下

which of the follwong , if true, could most appropriatedly cite proponents of the plan above as a piece of evidence for the soundness of their plan?

还请NN看看...

自由的疑惑2：对于D，OG这样解释到：” and D by indicating that such an alternative is not by itself a solution to airport congestion. “ 自由结合了D这个选项，不是很明白含义，谢谢大家指教。

引用mindfree的原话:"

D is not as good because it does not offer a direct linkage between ground transportation and air traffic as the correct answer. "

这一点,感觉MINDEFREE说的有道理, 看来自由的英文功底真的是差的老远. 非常感谢MINDFREE和VINCENT0330的精辟分析, 两位对语法分析和逻辑分析都很出色,感谢两位朋友, 另外"预防"其实自由是想打成"语法".不好意思,让大家误会含义了.