Sound can travel through water for enormous distances, prevented from

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

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

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

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.

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.

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.

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

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.

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.

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.

We need a comma before a non-essential modifier - a modifier that states something extra about the noun or the sentence it modifies and can be omitted without changing the meaning of the rest of the sentence. Here "its acoustic energy...." is a non- essential absolute phrase modifier, and hence a comma is mandatory. Absolute phrase modifiers are always non-essential type.

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 correct answer is D. its acoustic energy prevented from dissipating by

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 ";".
First sentence: Sound can travel through water for enormous distances.
Second sentence: its acoustic energy prevented from dissipating by boundaries in the ocean created by water layers of different temperatures and densities.

Can anyone explain it to me?

Hi stanleygao, this structure is called absolute modifier and is just a phrase (not a clause/sentence). The structure of an absolute modifier typically is:

Noun (its acoustic energy) + Noun modifier (prevented from dissipating....).

Absolute modifiers are quite frequently tested on GMAT and so, test takers need to make themselves comfortable with this usage.

p.s. Our book EducationAisle Sentence Correction Nirvana discusses Absolute Modifier, its application and examples in significant detail. If someone is interested, PM me your email-id; I can mail the corresponding section.

In Manhattan's SC correction guide, under chapter 10 (page 197) of 5th edition:

"A comma by itself cannot connect two complete sentences (main clauses)"
eg. WRONG: Earl walked to school, he later ate his lunch.


Isn't C doing a similar thing here? connecting two complete sentences?

The second element is not a clause. It's an absolute phrase. One way to see that is to check whether prevented is a (complete) verb. If we try saying its acoustic energy prevented from dissipating by boundaries, we can see that prevented does not seem to be "combining" with acoustic energy.

Compare these two structures:

Its acoustic energy prevented from dissipating by boundaries.

Its acoustic energy is prevented from dissipating by boundaries.

Clearly, the second is complete, but the first is not.