GWD26-37

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raikey

vote for C

做题时在B和C之间犹豫(其余选项意思不对),后觉得having ...done...比较罗嗦,选C.

qianrene

我选E

chamcham

C

Here is what I saw in another popular forum:

D isn't so bad. Sound's "acoustic energy [is] prevented from being dissipated..." But why use the wordy passive transitive "being dissipated" when the one-word active intransitive "dissipating" is perfectly acceptable? In any case, what really turned be off to D is "as a result of." It is far more direct and precise to say "prevented by" than "prevented as a result of."

I see nothing wrong with C. It's certainly not a run-on sentence: there's no conjugated verb after the comma. "Prevented" is the past participle. The second part of the sentence is saying that boundaries in the ocean prevent sound's acoustic energy from dissipating.

The idea could be conveyed in two sentences:

Sound can travel through water for enormous distances. Boundaries in the ocean... prevent its acoustic energy from dissipating.

Combine the sentences and you get:

Sound can travel through water for enormous distances, its acoustic energy prevented from dissipating by boundaries in the ocean....

[此贴子已经被作者于2007-6-18 17:14:31编辑过]

sophiafinn

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mygk

后面是个名词，表明是句末同位语，是优选答案

点虫虫

doing的问题是因为前面的搭配吧,prevent...from doing?

carolinelmf

E项是正确的。声波本身的特质就是在水中的衰减非常小，boundaries会令声波衰减，而不是让声波不衰减，C，D项错在把boundaries当好人了。

preventing作伴随状语，把它调到句首就十分容易理解了。

Preventing its acoustic energy from dissipating by boundaries in the ocean created by water layers of different temperatures and densities, sound can travel through water for enormous distances.

逻辑上可以理解为：因为能量不被水减弱，声波可能传千里。

hollygrail

句子的意思是 boundaries prevent sound from dissipating its acoustic energy (从修改前原文中分析的意思)
disspate可以做vt.,vi.
未改动的句子有这个 (sound) dissipating its energy,不是很好,因为并不是sound削弱了energy而是其他东西(阻力?)削弱.
出题者做了改动后有两项可以入选B和C
C: boundaries prevent energy from dissipating
B: boundaries prevent sound from having energy dissipated
have something stolen有 (somebody else) stoled something的意思,如果用在这里有(something else) dissipate energy,如果GMAT认可这种用法,就狠了.说明他把原来的句子甚至优化了.

eileenmu木

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