Sound can travel through water for enormous distances, prevented from

Reading the discussion on this thread surely took my head for a spin. I don't know if I could also blame the time (its past midnight here). Anyways, I will give my two cents on this discussion.

But first of all, Marcab, welcome back!!

After reading through your doubts here, I think I can figure out why you are confused between choices B and C. There is two-fold reason for your confusion

1: Use of verb-ed modifier - verb-ed modifiers modify the closest noun phrase. In the context of GMAT, I have not seen a single question in which these modifiers modify the preceding clause. Yes in normal English usage, we do use these modifiers the way we use verb-ing modifiers to modify the preceding clause. Now that being said, your explanation about the use of "prevented" to modify the subject "sound" is not correct.

2: The use of modifier "by boundaries" - The way these choices are constructed lead to two different modifications in the sentence.

Choice B: Sound can travel through water for enormous distances, prevented from having its acoustic energy dissipated by boundaries in the ocean created by water layers of different temperatures and densities.

prevented from what?
prevented from having its acoustic energy what?
prevented from having its acoustic energy dissipated by what?
prevented from having its acoustic energy dissipated by boundaries.
Per the logical intended meaning, do the boundaries "dissipate the energy"? No. Boundaries prevent the dissipation.
Another thing - "by boundaries" is too far away from "prevented" to modify it.



Now let's look at choice C

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

prevented from what?
prevented from dissipating
prevented by what?
prevented by boundaries
so together we have - prevented from dissipating by boundaries
By contrast, in this choice, "by boundaries" is in good proximity of "prevented" to modify it correctly.

I hope this helps with the meaning clarification!
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checked on other forums and OA is C.

"dissipating by" is the correct idiom.

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 - changes the meaning. "Sound" is not prevented. "acoustic energy" is prevented from dissipating
B. prevented from having its acoustic energy dissipated by - same as A
C. its acoustic energy prevented from dissipating by - CORRECT
D. its acoustic energy prevented from being dissipated as a result of - wordy and 'being' is incorrect.
E. preventing its acoustic energy from dissipating by - same as A. This sounds like sound is preventing its accoustic energy.

Hi honchos,

This is in response to your PM.

Let’s first understand the meaning of the original sentence:
• Sound can travel through water for enormous distances,
o prevented from dissipating its acoustic energy as a result of boundaries in the ocean created by water layers of different temperatures and densities.

MEANING

• This sentence represents a fact that sound can travel through water for long distances.
• Then it tells the reason behind this fact: It says that the water layers of different temperatures and densities create boundaries in the ocean. These boundaries prevent the acoustic energy of sound form dissipating.
So, according to the original sentence the action of ‘preventing’ is done by the boundaries created by water layers.


Now, let’s take a look at OPTION E:
• Sound can travel through water for enormous distances,
o preventing its acoustic energy from dissipating by boundaries in the ocean created by water layers of different temperatures and densities.

VERB-ing MODIFIER
If a verb-ing modifier is placed after a clause and it is preceded by a comma, then it modifies the preceding clause. This modifier makes sense with the subject of the preceding clause, and it:
i) Either provides additional information about the preceding clause
ii) Or presents the result of the preceding clause.

• Tom killed the snake, using a stick. (Additional Information)
• The recession adversely affected the company’s business, reducing its profits by 50%. (Result)
In both the above sentences, the subject makes sense with the verb-ing modifier, since it is clear from these sentences that “Tom used the stick” and “The recession reduced the profits”.

Now, in the given sentence, the verb-ing modifier ‘preventing’ presents additional information about the preceding clause. Also, the subject ‘sound’ should make sense with ‘preventing’.
So, this sentence conveys the meaning that sound prevents its acoustic energy from dissipating. This is not the intended meaning of the original sentence since the boundaries did the action of preventing, not the sound.


Hope this helps!
Deepak
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Hi fameatop,

This is in response to your PM.

Let's analyze the structure of Choice C: Sound can travel through water for enormous distances, its acoustic energy prevented from dissipating by boundaries in the ocean created by water layers of different temperatures and densities.

There is no doubt that the portion before the comma is an Independent Clause with "Sound" as a Subject and "can travel" as a Verb.
Now let's look at the latter portion of the sentence.

its acoustic energy prevented from dissipating by boundaries in the ocean created by water layers of different temperatures and densities.

This structure is actually Noun + Noun Modifier that modifies the preceding clause.
Noun = its acoustic energy
Noun Modifier = prevented from dissipating...
(For more on this topic, please read the article in this link: noun-noun-modifiers-before-we-start-discussing-about-the-137292.html)

What does this portions says? It says that its (sounds) acoustic energy prevented. Now does it make sense that the sound itself prevents its acoustic energy? No, it does. Now read further. "its acoustic energy prevented... by water layers of different temperatures and densities." Now, does this make sense? Yes, it does. This structure actually provided the characteristic of the acoustic energy in that it says that this acoustic energy is prevented from dissipating by water layers of different temperatures and densities.

In original Choice C, "prevented" CANNOT be a passive voice also because it is not preceded by a helping verb such as is/am/are/was/were etc. So, prevented here id just a verb-ed modifier, a Noun Modifier that modifies the preceding noun entity "its acoustic energy". Together this modified noun + noun modifier modifies the preceding clause by presenting the reason for the main action in the sentence.

Remember, we are talking about the CORRCT OFFICIAL answer choice. It cannot have a grave error of fragment.

Hope this helps.
Thanks.
Shraddha
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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.

The independent clause is "Sound can travel through water for enormous distances" and rest is the modifier.

A. prevented from dissipating its acoustic energy as a result of -> prevented is past participle modifier (verbed modifier) and should modify the nearest noun -> enormous distances -> doesn't make sense.

B. prevented from having its acoustic energy dissipated by -> Same issue as that of A)

C. its acoustic energy prevented from dissipating by -> correct as prevented is modifying the "its acoustic energy" - a noun

D. its acoustic energy prevented from being dissipated as a result of -> dissipating not as a result of boundaries of ocean but because of boundaries of ocean

E. preventing its acoustic energy from dissipating by -> comma + verbing modifier attaches to the subject of the previous clause which means Sound itself is preventing its acoustic energy which is ridiculous.

Dear Friends,

Here is a detailed explanation to this question-

Meaning is crucial to solving this problem:
Understanding the intended meaning is key to solving this question; the intended meaning of this sentence is that sound can travel through water for enormous distances because its acoustic energy is prevented from dissipating by boundaries in the ocean created by water layers of different temperatures and densities.

Concepts tested here: Meaning + Modifiers + Verb Forms

• In the “phrase + comma + noun” and “noun + comma + phrase” constructions, the phrase must correctly modify the noun; this is one of the most frequently tested concepts on GMAT sentence correction.
• The introduction of the present participle ("verb+ing"- “preventing” in this case) after comma generally leads to a cause-effect relationship.

A: This answer choice incorrectly modifies "prevented from dissipating its acoustic energy...", leading to an incoherent meaning; the intended meaning is that sound can travel through water for enormous distances because its acoustic energy is prevented from dissipating by boundaries in the ocean created by water layers of different temperatures and densities; remember, in the “phrase + comma + noun” and “noun + comma + phrase” constructions, the phrase must correctly modify the noun.

B: This answer choice incorrectly modifies "prevented from having its acoustic energy...", leading to an incoherent meaning; the intended meaning is that sound can travel through water for enormous distances because its acoustic energy is prevented from dissipating by boundaries in the ocean created by water layers of different temperatures and densities; remember, in the “phrase + comma + noun” and “noun + comma + phrase” constructions, the phrase must correctly modify the noun. Further, Option B uses the passive voice construction "prevented from having its acoustic energy dissipated", leading to awkwardness and redundancy.

C: Correct. This answer choice avoids the modifer error seen in Options A and B and the verb form error seen in Option E, as it uses the phrase "its acoustic energy prevented from dissipating", correctly modifying the preceding clause to convey the intended meaning - that sound can travel through water for enormous distances because its acoustic energy is prevented from dissipating by boundaries in the ocean created by water layers of different temperatures and densities. Further, Option C is free of any awkwardness or redundancy.

D: This answer choice uses the needlessly wordy phrase "prevented from being dissipated as a result of", leading to awkwardness and redundancy.

E: This answer choice alters the meaning of the sentence through the phrase "preventing its acoustic energy from dissipating"; the use of the "comma + present participle ("verb+ing" - "preventing" in this sentence) incorrectly implies that sound can travel through water for enormous distances and as a result, sound prevents its acoustic energy from dissipating due to boundaries in the ocean created by water layers of different temperatures and densities; the intended meaning is that sound can travel through water for enormous distances because its acoustic energy is prevented from dissipating by boundaries in the ocean created by water layers of different temperatures and densities; remember, the introduction of the present participle ("verb+ing"- “preventing” in this case) after comma generally leads to a cause-effect relationship.

Hence, C is the best answer choice.

To understand the concept of "Phrase Comma Subject" and "Subject Comma Phrase" on GMAT, you may want to watch the following video (~1minute):



To understand the concept of "Comma + Present Participle for Cause-Effect Relationship" on GMAT, you may want to watch the following video (~3 minutes):



All the best!
Experts' Global Team
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Step 1)

I noticed the first phrase before the comma was a complete thought: "Sound can travel through water for enormous distances"

So that means what follows the comma must be a descriptive phrase.

Step 2)

I noticed one of the answer choices was a descriptive -ING verb phrase - so I ask myself: does it make sense that the SOUND is the one that is PREVENTING its acoustic energy from dissipating by X?

No - it does not make sense that sound prevents something.

So that leads me to look at (C) and (D) more carefully.

Step 3)

Between these two choices, (C) is clearly simpler - with fewer words. It also does not have the red flag word "being"in there. So at this point, (C) appears to be the best of the available answer choices.

Quoting your doubt


The trick in order to identify absolute phrase is to check whether the clause contains a verb or not. If the clause contains a verb then it cannot be the AP.
Moreover, an AP will always answer HOW of the preceding clause.
Hope that helps.

Responding to a PM
The basic difference between B and C is the subject.
In B, subject is "sound'. So B implies that "sound" is prevented from having its acoustic energy bla bla bla.
C, in which the subject is "acoustic energy", on the other hand implies that "sound's acoustic energy is prevented from dissipating bla bla bla". Moreover the construction that is used in C is of "absolute phrase". Whenever you come across this construction, just ask HOW after the clause just before the absolute phrase. If the Absolute phrase answers your "how" question correctly in exact words then that choice is the answer.
"Sound can travel through water for enormous distances". HOW?
ANSWER: its acoustic energy prevented from dissipating by boundaries in the ocean created by water layers of different temperatures and densities.

Hope that helps.
Let me know if more clarification is required.

The second part after comma is not an independent clause; it is an absolute phrase. Absolute phrases consist of the following structure:
noun (or noun phrase) + noun (noun phrase) modifier

Absolute phrase modifiers modify the adjacent clause as a whole.

Here,
noun phrase= its acoustic energy
noun phrase modifier = prevented from dissipating (prevented is a past participle, not a verb)

The absolute phrase modifier its acoustic energy prevented from dissipating... modifies the clause Sound can travel through water for enormous distances.

Thus the use of comma is alright. Another example of absolute clause is as follows:

His held head high, he left the room.

The underlined part here is the absolute phrase.

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.

1) prevented from dissipating its acoustic energy as a result of
2)prevented from having its acoustic energy dissipated by
3) its acoustic energy prevented from dissipating by
4) its acoustic energy prevented from being dissipated as a result of
5) preventing its acoustic energy from dissipating by

The whole issue here is about the modification of the comma plus verb+ed modifier' 'prevented'. It is an error to think that the participle 'comma plus prevented' can modify the distant 'sound'. A past participle modifier separated by a comma and intercepting a clause can only modify the nearest noun namely distances, which is devoid of any meaning in the contest.

Therefore, we can safely dump A and B.

Nor is it any more sensible to say that sound prevented its own acoustic energy from dissipation in order to be able to travel long distances as in E.

Between C and D, it doesn't take too long to kick out D for using the phrase 'being dissipated' as a modifier. Therefore, it is a cake-walk for C.
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absolute phrase in c shows the context of main clause.

the meaning in c is

in the context that, energy of sound is prevented from dissipating by...., sound can travel a long distance.

the meaing relation between absolute phrase, and main clause should be understood clearly. Unforturenately, there is no grammar book which said about this point.

any one know about the meaning relation between absolute phrase and main clause, pls, share. sc is meaning game. this means we have to diferentiate between the distorted meaning and intended meaning and so, we have to know this meaning relation.

A. prevented from dissipating its acoustic energy as a result of
comma+ed modifier modifies the closest noun - thus incorrect

B. prevented from having its acoustic energy dissipated by
same error as in A.

C. its acoustic energy prevented from dissipating by
noun+noun modifier used correctly.

D. its acoustic energy prevented from being dissipated as a result of
being is correctly used in 2 cases:
1. when it is used as a noun
2. when it is used in a passive voice construction
none of these cases is here, hence incorrect.

E. preventing its acoustic energy from dissipating by
comma+ing modifier modifies entire clause by associating itself with subject and verb of the clause preceded. thus, in this case it is incorrectly used.

This question popped up on our Ask Me Anything About SC thread. Reposting it here just in case it helps somebody else:


The most straightforward decision point here is meaning. If something dissipates, it disperses on its own -- like steam, for example.

If something is being dissipated, it sounds as though there's an outside force causing the dispersion -- a farmer spreading seeds, perhaps. In this case, we're talking about the acoustic energy of sound. It makes far more sense to write that this energy disperses on its own than that a third-party is sprinkling bits of sound through the air. Because "being dissipated" is illogical here, we can eliminate (D).

Note also, that "by" is a cleaner more concise way of expressing "as a result of." So while "as a result of" isn't inherently wrong, in a side-by-side comparison with "by," it's a clear loser.

I hope that helps!
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Hi crazykaushik, a run-on sentence construction is when two Independent clauses are connected by a comma.

In option C, the following portion of the sentence is not an Independent clause:

its acoustic energy prevented from dissipating by boundaries in the ocean created by water layers of different temperatures and densities.

In fact, it is not even a clause. This kind of a construct is called absolute modifier and has the following structure:

i) Noun (its acoustic energy) +
ii) Noun-modifier (prevented from dissipating by boundaries in the ocean created by water layers of different temperatures and densities)

This is very frequently tested on GMAT and so, it might be a good idea to make yourself comfortable with this structure.

Our book EducationAisle Sentence Correction Nirvana discusses Absolute modifiers, their application and examples in significant detail. If someone is interested, PM me your email-id, I can mail the corresponding section.
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Dear stanleygao,

Two things about the query you raised.
1. "I am confused with the sentence construction of this question. It looks like there are two complete sentences without a proper conjunction of "and" or ";". "
GMAT doesn't allow 2 "two complete sentences"(sentences with subject and verb) to be connected with a conjunction, but rather they are combined with a semicolon(;).
2. In the above mentioned sentence. The first portion before the comma is a clause, but the second portion is a absolute phrase.
2 things here:
1. There isn't a verb in the second portion at all. "Prevented" is a past participle, and dissipating is a present participle, but not active verbs.
2. Absolute phrase:
The part after the comma (called the absolute phrase) has the following characteristics:
1. It starts with a possessive form (his, her, its, their etc.)
2. It only adds to the meaning (just additional or filler information). It is not core information.
3. It contains no verb (it is a phrase).
4. It is adverbial in nature (it goes back to the whole clause, not to a specific noun).

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.

E. preventing its acoustic energy from dissipating by
What is its referring to? Sound or Water? antecedent is not clear E is wrong.

C. its acoustic energy prevented from dissipating by
This is called an absolute phrase and modifies the entire clause that precedes it.

Read about absolute phrases on gmatclub and magoosh

In the correct option C, what ensures that "its" correctly refers to 'sound',but not to 'water'?


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


1. Technicals: The word 'acoustic' refers to sound and therefore acoustic energy means sound contained in sound waves. On the contrary, water's energy refers typically to the electricity generated from water.

2. Grammar. A pronoun's first choice of antecedent is always the subject, and if the subject doesn't suit, it may refer to a direct object or an object of the preposition that may be near to it. All in all, the logical meaning rather than the placements plays the decisive role.
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Hello, lakshya14. We are getting to be virtual pals, as often as we are crossing paths. Choice (E) has a fatal flaw that does not make logical sense. Try inserting it into the shell of the sentence:

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

What, exactly, is preventing the acoustic energy of sound from dissipating? Would it make sense to say that sound prevents its own acoustic energy from dissipating? Is there some sort of built-in self-preservation mechanism that we need to be aware of? Are we then to understand that boundaries in the non-negotiable part of the sentence act as sound-dissipators? If so, that is actually the opposite of what the shell of the sentence would suggest. Would it not make more sense for a boundary to contain something? And if something is contained in water, then it does not dissipate, and that is what we are after. Compare to (C):

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

Aha, so straightened out, with the sentence in a more active voice, we understand that boundaries in the ocean prevent the acoustic energy of sound from dissipating, thereby allowing sound to travel through water for enormous distances. That makes perfect sense, and we did not get tangled up in any seaweed following the logic.

I hope that helps. If you need further clarification, just ask.

- Andrew
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