Hey gmat ninja,

Was wondering if you could break down c and d for me here as you usually do - question here: https://gmatclub.com/forum/sound-can-tr ... 77588.html

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

Cheers

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,

Can you please tell me as to how to figure out if the modifier is modifying the last word, the first word of the noun phrase or the whole clause?

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Hey GMATNinja, no further questions but ended up sitting the gmat today and came out with a 720 (v41) - thank you for the help and keep doing what you're doing!

I happened to read a statement, this makes me want to ask this to an expert, and I picked my favourite one for this...
GMATNinja
This is my Uncle John, who lives in NYC [Non Essential] it is fine
This is my Uncle John that lives in NYC [Essential] .. is this sentence correct ?or we need to use "who" for "uncle John"..
Thank you

Hi GmatNinja,

I'm facing trouble with this official question.

The increased popularity and availability of televisions has led to the decline of regional dialects, language variations which originate from diverse ethnic and cultural heritages and perpetuated by geographic isolation.


(A) which originate from diverse ethnic and cultural heritages and perpetuated

(B) that originated from diverse ethnic and cultural heritages and perpetuated

(C) originated from diverse ethnic and cultural heritages and perpetuated

(D) originating from diverse ethnic and cultural heritages and perpetuated

(E) originating from diverse ethnic and cultural heritages and perpetuating

I'm confused between C & D. I know the rule that in //ism, the modifiers can be in different form, however, I'm facing trouble recognizing why originated is not a modifier but verb ?

Thankyou!!

Hey man, is D the answer ?

the list is false parallelism, carefully re-read the sentence and break it down..

The increase and popularity of something has led to
1. decline of regional dialects
---------- these are originating from two things
a) diverse ethnic
and
b) cultural heritages

this list is over now.. (see there are no commas too, between these lists..just "and" a parallelism marker..
X------------- X
now the original list..which is affected by the subject of sentence (increase and popularity)

2. perpetuated by geographic isolation

this according to me should be the ideal list, as "diverse ethnic and cultural heritages" can't be parallel to "perpetuated" or "decline" ; these two can be parallel, as they are similar words or "verbs" if you like jargon :P

/// my question is why we don't see a "have" as the verb of the subject, and "are" before "perpetuated" ... is this question from an official source ?

Yes, GMATPREP.

GMATNinja egmat daagh please help!

Hi Charles,

I faced a question in a mock that I was unable to solve. Can you please provide an explanation for this?

The discovery that Earth's inner core rotates independently of and more quickly than Earth's outer layers is responsible for advancing studies of the flow of heat from the inner through the outer planet and of the formation and periodic reversal in direction of Earth's magnetic field.

1. core rotates independently of and more quickly than Earth's outer layers is responsible for advancing studies of the flow of heat from the inner through the outer planet and of the formation and periodic reversal in direction of Earth's magnetic field

2. core rotates independently of and more quickly than Earth's outer layers is responsible for advancing studies of how heat from the inner core flows through the outer planet, and the formation and periodic reversal in direction of Earth's magnetic field

3. core rotates independently and more quickly than Earth's outer layers are responsible for advancing studies of how heat from the inner core flows through the outer planet, and how Earth's magnetic field forms and the periodic reversal of its direction

4. core, rotating independently and more quickly than Earth's outer layers, are responsible for advancing studies of the flow of heat from the inner through the outer planet, and the formation and periodic reversal in direction of Earth's magnetic field

5. core, rotating independently of and more quickly than Earth's outer layers, is responsible for advancing studies of the flow of heat from the inner through the outer planet and of how Earth's magnetic field forms and the periodic reversal of its direction

Correct answer is [A], and i can't understand why?

Hey,
if you marked B, then you are aware of most of the errors in other options : usage of "are" when subject is singular ("the discovery") and, "core, rotating ...." changes the meaning in a funny way.

But between, B and A
look at the last part of B) "and the formation and periodic reversal in direction of Earth's magnetic field"

This says that discovery is responsible for the "formation and periodic reversal in direction " .....

A discovery can't change something's direction ...
Therefore, A ) also with a parallel list of "of" is the right answer..

But I picked B), at first - just to tell you- you are not alone, its a tricky one.
Hope the experts clear more doubts, if any.

Hi GMATNinja,

In Manhattan SC 4th edition, it is given that -
Preposition + Simple Gerund is a verb modifier.
Ex. I lifted the weight by concentrating.
This modifier applies to both the verb and the verb's subject.
"by concentrating" is modifying the verb "lifted" and subject of verb makes sense with modifier - I was concentrating.

But I am unable to apply the above in ex - Mother keeps children from watching television .
"from watching television" is modifying the verb "keeps", but it does not make sense with subject "Mother".

Please explain.

Fundamentally, I don't think there's anything wrong with using "that" to describe a person or people. So either of these are reasonable:

• "The man who consumed too much bourbon in his youth mistook his toddler for a stuffed ostrich."
• "The man that consumed too much bourbon in his youth mistook his toddler for a stuffed ostrich."

Both seem fine to me. Just as importantly, I've never seen an official GMAT SC question that forces you to choose between "who" and "that."

For whatever it's worth, "who" can be the beginning of either an essential or non-essential modifier:

• "The man who consumed too much bourbon in his youth mistook his toddler for a stuffed ostrich." -- Essential modifier: without the modifier, we apparently wouldn't know which man mistook his toddler for a stuffed ostrich.
• "The man, who consumed too much bourbon in his youth, mistook his toddler for a stuffed ostrich." -- Non-essential modifier: the part between the commas appears to be extra information, and without it, we'd still understand which man has problems recognizing his own kid.

As I've mentioned multiple times on this thread, the GMAT can't easily test the distinction between essential and non-essential modifiers, so I wouldn't worry about them too much.

I hope this helps!
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For starters, I can't quite figure out how this would reasonably be useful for answering an actual GMAT SC question. Sure, preposition + gerund constructions are common in English; I've also never thought about them for even a moment in almost 20 years of teaching test prep and English. So unless you can find an official GMAT question that uses this issue as a major decision point, it's probably not worth worrying about.

I also think you might have answered your own question: you said that the preposition + gerund is a verb modifier, right? Basically, it gives more information about the action in the sentence. That's true if we say "I lifted the weight by spraining multiple muscles", and it's also true if we say "Mother keeps children from watching television." In the latter example, "from watching television" is giving us more information about what, exactly, Mother is doing.

But again: I'm not sure how this issue would lead you to make mistakes on the GMAT.

I hope this helps a bit!
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SC is less about why the correct answer is right than why the incorrect options are wrong. The key here, as Shrey9 notes below, is the parallel construction demanded by the multiple uses of "and," and how this construction shapes the meaning of the sentence.

First, take a look at (A), stripped down:

"The discovery [long modifier] is responsible for advancing studies of the flow of heat from the inner through the outer planet and of the formation and periodic reversal in direction of Earth's magnetic field."

Because "of the formation" ("preposition + noun") comes right after "and" we want a similar construction to precede it. In this case, we find "of the flow of heat." Now we want to ask ourselves if these two elements are logically parallel. And it makes perfect sense that the discovery is responsible for advancing studies of two things: (1) of the flow of heat and (2) of the formation and reversal of the earth's magnetic field. So keep (A).

Now compare that with all the other options. (B), (C), and (D) all lack the "of" before "formation." Is the preposition absolutely mandatory in a grammatical sense? No. But because the sentence is so complicated, it becomes very very difficult to see that the discovery is responsible for advancing studies of two separate elements if we don't include "of" before both of them. This confusion is enough to get rid of these options, but if you're skeptical, let's find a more concrete error in each:


Here, the "comma + and" creates the expectation that we're going to be treated to new information, potentially unrelated to what we've seen thus far. Put another way, it sounds as though "the discovery" is responsible only for advancing studies of how heat flows, and then there's this new clause about "the formation." But there's no verb to go with "formation!"

When we look back at the sentence, it appears that the discovery is responsible for "advancing studies" and for "the formation" itself. My physics is a little rusty, but I'm confident that a discovery can't be responsible for the formation of a magnetic field. That's illogical, so get rid of (B).

Both (C) and (D) have the same subject-verb agreement error: "The discovery... are responsible," so those are out.

And here's (E):
First, it sounds like the "earth's inner core" is itself responsible for advancing studies. Worse, there's no main verb here to go with the subject "the discovery." So this is illogical and ungrammatical. (E) is out, and (A) is our winner.

I hope that helps!
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Hi Mr.Charles
I would be happy if you answer this question.

https://gmatclub.com/forum/neanderthals ... l#p2335090



Neanderthals had a vocal tract that resembled those of the apes and so were probably without language, a shortcoming that may explain why they were supplanted by our own species.
correct =(B) Neanderthals had a vocal tract resembling an ape’s



please explain how "resembling" can modify a thing in the past ??????? I SAW "-ing" modifier only in present tense be correct and many question wrong because of using -ing modifier in past .......BUT in this case it use for past tense !

in other word = "a vocal tract that resemble an ape's" or "a vocal tract that resembled an ape's" which is correct.?
tnx in advance.
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Hi Charles,

I am going to give my GMAT exam in December. I have given three mock tests and in those, I have scored 590(Q40, V29-Official GMAT) in first, 560(Q33 V31) in second and 570(Q33,v31).
While I was analyzing these mocks, I scored poorly in SC and RC.
So can you pls suggest my a study plan for SC and RC for the next three month.What basics I need to cover and in how much time I should cover those topics
I have 3 hours to Study verbal on a weekday and 6 hours on weekends
I don't have any material right now except GMAT club SC book.

please help me in creating my study plan for the next three months

Hi GMAT Ninja,

I am confused regarding an idiom:
Distinguish x from y
Distinguish between x and y

Are they correct?

If they are, then do they have any specific usage?

Sincerely,
Thanks.

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let me answer you quickly ..... I am sorry ninja !
if you see on gmat go for second Distinguish between x and y
according to Mgmat and og =
https://gmatclub.com/forum/in-his-resea ... 39274.html
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When releasing an animal that has lived in captivity back into a wild environment, zoologists can never be sure whether it will successfully adapt to its new habitat.

A. releasing an animal that has lived in captivity back into a wild environment, zoologists can never be sure whether it will successfully adapt to its new habitat

B. an animal that has lived in captivity is released back into a wild environment, zoologists can never be sure if it will successfully adapt to its new habitat

C. releasing an animal back into a wild environment that has lived in captivity, zoologists can never be sure whether it will successfully adapt to its new habitat

D. an animal is released back into a wild environment that has lived in captivity, zoologists can never be sure if it will successfully adapt to its new habitat

E. an animal that has lived in captivity is released back into a wild environment, zoologists can never be sure whether it will successfully adapt to its new habitat or not

The answer is A but I marked E - is using ing form of verb with When appropriate? Why is E wrong?