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655-705 Level|   Meaning/Logical Predication|   Modifiers|   Verb Tense/Form|                           
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Sound can travel through water for enormous distances, prevented from 30 May 2020, 17:39
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gagan03
In C is the usage an example of Noun plus Noun modifier?
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Hello gagan03,
Thank you for the query. :-)

Yes, you identified it correctly. The structure indeed is a Noun + Noun Modifier.

Following is the link to one of the most popular articles on GMAT Club that details all about this modifier. Please go through the same for the correct usage and more official examples of this super flexible modifier:

https://gmatclub.com/forum/noun-noun-modifiers-the-most-versatile-modifier-137292.html



Hope this helps. :-)
Thanks.
Shraddha
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Sound can travel through water for enormous distances, prevented from 30 May 2020, 18:18
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lakshya14
Hi, what's the problem with (E). The verb-ing is modifying the subject of the preceding clause, i.e. "sound". How can it be better than (C)?
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Hello lakshya14,

I know that your question has already been answered, and quite magnificently. Nonetheless, here are my two cents.

So let's look at the original sentence first: Sound can travel through water for enormous distances, prevented from dissipating its acoustic energy as a result of boundaries in the ocean created by water layers of different temperatures and densities.

The first part of this sentence states a fact/general information about sound. The second part of the sentence presents the reason for that fact. So understanding what the sentence intends to convey is not difficult.


Now, Choice A is incorrect because it seems to suggest that sound can travel through water for really long distances because the sound is prevented from dissipating its own acoustic energy because of the boundaries in the oceans mentioned in the sentence. This certainly is not the intended meaning. It is the acoustic energy of the sound that is prevented from dissipating. Hence, this choice is incorrect.


Choice E, with the usage of the action modifier comma + preventing... says that sound prevents its acoustic energy from dissipating. But this is not correct because we know that the boundaries in the oceans prevent the acoustic energy from dissipating. Hence, this choice is incorrect.

Choice C is the correct answer choice because the Noun + Noun Modifier "its acoustic energy prevented..." correctly presents the reason why sound can travel really long distances in water.


You can go through our very famous article on the usage of the comma + verb-ing modifier that acts as an action modifier. The article details the conditions when the usage of this modifier is considered correct.

https://gmatclub.com/forum/usage-of-verb-ing-modifiers-135220.html#p1101074



Hope this helps. :-)
Thanks.
Shraddha
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Sound can travel through water for enormous distances, prevented from 15 Jun 2020, 04:24
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The reason why I didn’t choose C or D is because I thought the underlined part must be preceded by a semicolon. Can anyone explain why it doesn’t need to be?

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GMARKET
The reason why I didn’t choose C or D is because I thought the underlined part must be preceded by a semicolon. Can anyone explain why it doesn’t need to be?

Posted from my mobile device
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Hello, GMARKET. The reason neither (C) nor (D) requires a semicolon is that the part after the comma is known as an absolute phrase. Notice the lack of a verb in the form of to be:

Quote:

Sound can travel through water for enormous distances, prevented from dissipating its acoustic energy as a result of boundaries in the ocean created by water layers of different temperatures and densities.

(C) its acoustic energy prevented from dissipating by

(D) its acoustic energy prevented from being dissipated as a result of
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That is, for either phrase to become a clause, you would need to see an is:

its acoustic energy is prevented from dissipating by

For more on absolute phrases, check out this article on Grammar Bytes! (The third example follows a similar construct as the sentence above.) If you have further questions, feel free to ask.

Good luck with your studies.

- Andrew
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Sound can travel through water for enormous distances, prevented from 23 Aug 2020, 01:28
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egmat

How option C can be correct? we know that comma sholud be preceded by one of the FANBOYS.
Can you please explain?

(c) its acoustic energy prevented from dissipating by

Thank you!
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Sound can travel through water for enormous distances, prevented from 05 Sep 2020, 15:24
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mike egmat GMATNinja
Can you please explain why the use of *ITS* is correct in option C, I rejected option C because I thought its can refer back to SOUND and WATER Both.

Sound can travel through water for enormous distances, prevented from dissipating its acoustic energy as a result of boundaries in the ocean created by water layers of different temperatures and densities.


(A) prevented from dissipating its acoustic energy as a result of

(B) prevented from having its acoustic energy dissipated by

(C) its acoustic energy prevented from dissipating by

(D) its acoustic energy prevented from being dissipated as a result of

(E) preventing its acoustic energy from dissipating by
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Sound can travel through water for enormous distances, prevented from 08 Nov 2020, 06:27
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Economist
Sound can travel through water for enormous distances, prevented from dissipating its acoustic energy as a result of boundaries in the ocean created by water layers of different temperatures and densities.


(A) prevented from dissipating its acoustic energy as a result of

(B) prevented from having its acoustic energy dissipated by

(C) its acoustic energy prevented from dissipating by

(D) its acoustic energy prevented from being dissipated as a result of

(E) preventing its acoustic energy from dissipating by
Show more

This question is based on Modifiers.

Options A and B are participle modifiers that modify ‘distances’. It is not distances that are prevented from dissipating their acoustic energy. Furthermore, the phrase “as a result of” is not as appropriate as the preposition ‘by’. So, Option A can be eliminated.

The participle ‘having’ further complicates the meaning in Option B. It implies that there is some other agent dissipating the energy. This agent would be ‘boundaries’, so the meaning is illogical. So, Option B can also be eliminated.

In Option E, the meaning conveyed is that sound prevents its acoustic energy from dissipating. This meaning is illogical as it is ‘boundaries’ that prevent the energy from dissipating. So, Option E can also be eliminated.

Options C and D have a different construction, that of a noun + noun modifier.

Option D is wordy. It also has the phrase “as a result of”. The phrase “prevented from dissipating by boundaries” is more appropriate than “prevented from dissipating as a result of boundaries”. So, Option D can be eliminated.

Option C is concise and clear. Therefore, C is the most appropriate option.

Jayanthi Kumar.
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Sound can travel through water for enormous distances, prevented from 06 Mar 2021, 10:39
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Sapnilbhatnagar
mike egmat GMATNinja
Can you please explain why the use of *ITS* is correct in option C, I rejected option C because I thought its can refer back to SOUND and WATER Both.
...
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The short answer is that pronoun ambiguity isn't an absolute rule on the GMAT (for more on that, check out this video). And from the context, we can logically infer that the "it" refers to "sound" and not "water."

Generally speaking, you don't want to eliminate something just because there's a little pronoun ambiguity. Look for other decision points and then, if needed, you can use the ambiguity factor to vote the remaining choices up or down.

I hope that helps!
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Sound can travel through water for enormous distances, prevented from 07 Mar 2021, 09:51
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swadhakamal
egmat

How option C can be correct? we know that comma sholud be preceded by one of the FANBOYS.
Can you please explain?

(c) its acoustic energy prevented from dissipating by

Thank you!
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This is something that gets asked all the time... see if these two posts help answer your question:

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Sound can travel through water for enormous distances, prevented from 19 Jun 2021, 19:31
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AndrewN VeritasKarishma

I have a question in general related to the Difference between 'Absolute Phrase' and 'Noun+Noun Modifier'.

I read an article from egmat that Noun+Noun Modifier can modify:-
1. Nearest Noun before a comma.
2. Noun in Middle in a preceding clause.
3. Preceding clause (Absolute Phrase situation)

How to identify in a sentence that we have to use Absolute phrase or Case 1 and 2 as mentioned above??
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Sound can travel through water for enormous distances, prevented from Updated on: 11 Oct 2022, 00:30
Originally posted by KarishmaB on 20 Jun 2021, 23:28.
Last edited by KarishmaB on 11 Oct 2022, 00:30, edited 1 time in total.
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warrior1991
AndrewN VeritasKarishma

I have a question in general related to the Difference between 'Absolute Phrase' and 'Noun+Noun Modifier'.

I read an article from egmat that Noun+Noun Modifier can modify:-
1. Nearest Noun before a comma.
2. Noun in Middle in a preceding clause.
3. Preceding clause (Absolute Phrase situation)

How to identify in a sentence that we have to use Absolute phrase or Case 1 and 2 as mentioned above??
Show more

warrior1991 - Don't look for a list of rules because GMAT questions will not adhere to it. Look for context, what makes most sense in a certain situation and what options do I have available.
If you point to certain questions, I can tell you why a modifier modifies what it does and is the best option available.
If I tell you that a noun modifier usually modifies the directly preceding noun but could sometimes modify a far away noun too, how do you know whether a question falls under the "usual" or "sometimes" category? You don't. The only course of action we have is to see what works best in the context given to us.
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Sound can travel through water for enormous distances, prevented from 05 Sep 2021, 17:05
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Shouldn't there be a ";" between the two clauses if C is the correct choice? How can we separate 2 independent clauses using a ","?
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Sound can travel through water for enormous distances, prevented from 05 Sep 2021, 21:11
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Sound can travel through water for enormous distances, prevented from dissipating its acoustic energy as a result of boundaries in the ocean created by water layers of different temperatures and densities.


(A) prevented from dissipating its acoustic energy as a result of - V-ed modifier prevented modifies preceding noun "enormous distances" which does not make sense

(B) prevented from having its acoustic energy dissipated by - V-ed modifier prevented modifies preceding noun "enormous distances" which does not make sense

(C) its acoustic energy prevented from dissipating by - antecedent of "its" is "sound", hence sound's acoustic energy prevented from - clear meaning

(D) its acoustic energy prevented from being dissipated as a result of - "as a result of" is redundant

(E) preventing its acoustic energy from dissipating by - V-ing modifier modifies "sound", "sound preventing its acoustic energy from" - meaning incorrect
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Sound can travel through water for enormous distances, prevented from 06 Sep 2021, 06:16
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Rasalghul853
Shouldn't there be a ";" between the two clauses if C is the correct choice? How can we separate 2 independent clauses using a ","?
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Hi Rasalghul853,

You may find this post helpful.
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Sound can travel through water for enormous distances, prevented from 06 Sep 2021, 06:35
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Economist
Sound can travel through water for enormous distances, prevented from dissipating its acoustic energy as a result of boundaries in the ocean created by water layers of different temperatures and densities.
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(A) prevented from dissipating its acoustic energy as a result of
as a result isn't the perfect idiomatic usage by is far more perfect

(B) prevented from having its acoustic energy dissipated by
having isn't the right usage therefore out

(C) its acoustic energy prevented from dissipating by
idiomatic usage of disspating is right and by is also perfect

(D) its acoustic energy prevented from being dissipated as a result of
Being is a red flag and it's never correct therefore out

(E) preventing its acoustic energy from dissipating by
it's usage in the begining can be matched to sound however in the middle it's usage creates ambigiuty since we don't know whether it refers to road or sound therefore out

Therefore IMO C
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Sound can travel through water for enormous distances, prevented from 15 Oct 2021, 16:20
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doeadeer
GMATNinja could you please help with POE between B and C.

Many comments mark B incorrect on grounds that it is not modifying the subject, but Manhattan's thread on the same sentence claims that this cannot be grounds for elimination. Really confused here.
{...}
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As explained in this post, if something "dissipates", it disperses on its own, and it makes more sense to say that the acoustic energy disperses on its own than to say that something else disperses the acoustic energy. The acoustic energy wants to dissipate (like steam), but something (the boundaries) prevents the acoustic energy from dissipating. As a result, the sound is able to travel through water for enormous distances.

This is the perfectly logical meaning suggested by choice (C) -- the boundaries are doing the preventing, but the acoustic energy itself is the thing that would do the dissipating:

Quote:
(C) its acoustic energy prevented from dissipating by boundaries in the ocean...
Show more
Now look at (B):

Quote:
(B) prevented from having its acoustic energy dissipated by boundaries in the ocean...
Show more
Here the boundaries are preventing the sound from "having its acoustic energy dissipated" -- but having its acoustic energy dissipated by what? This passive construction suggests that there is some external thing that dissipates the energy, and that's not quite right.

You could also argue that, in (B), the boundaries are the thing that would dissipate the acoustic energy, but then we have the same issue: it makes more sense to say that the acoustic energy dissipates on its own. This interpretation would create another problem: if the boundaries are doing the dissipating, what's doing the preventing? We have no idea.

In (B), the meaning is open to interpretation, and neither interpretation works very well. In (C), the meaning is clear and makes perfect sense, so that's our winner.

I hope that helps!
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Sound can travel through water for enormous distances, prevented from 04 Nov 2021, 14:31
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Hi egmat

Regarding the choice C ı can't really understand how it somehow modifies the noun "sound" in the beginning of the first sentence. I do understand that the second portion in C is noun-noun modifier but ı can't really figure out how sound's acoustic energy modifies sound.

For instance in one of the examples in the great article you posted on noun-noun modifiers;
James created a magnificent design by using latest graphic design tools, expensive but super helpful devices developed especially for minute detailing and elaboration.

ı can easily see that "helpful devices..." refers to design tools because tools are devices, but sound and sound's acoustic energy doesn't really connect with each other in the meaning wise

Thank you for your explanation
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Sound can travel through water for enormous distances, prevented from 28 Nov 2021, 01:17
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I am not sure if this is a question of idiom but is clearly a meaning related one. "boundaries in the ocean created by water layers of different temperatures and densities" refers to a noun/object, thus, "as a result of" should not work here. "as a result of" should refer to a process (e.g., "The building fell as a result of demolition activities"). "dissipating by" works better for things/objects. That's my two cents
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Sound can travel through water for enormous distances, prevented from 09 Dec 2021, 08:24
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egmat
Please help.

When we talk about general truth we use simple present. Here why we are using " its acoustic energy prevented from dissipating by boundaries in the ocean created by water layers of different temperatures and densities." the bold are all -ed form.
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Sound can travel through water for enormous distances, prevented from 10 Dec 2021, 05:48
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thakurarun85

Please help.

When we talk about general truth we use simple present. Here why we are using " its acoustic energy prevented from dissipating by boundaries in the ocean created by water layers of different temperatures and densities." the bold are all -ed form.
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Hi thakurarun85.

Those -ed words are modifiers that describe how things are in the present. So, they communicate that, in the present, the "acoustic energy" IS "prevented from dissipating" and that the "boundaries in the ocean" ARE "created by water layers."

Thus, they do communicate general truths about the present.
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