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705-805 Level|   Comparisons|      
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Anandanwar
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Even in this age of conservation, cooking ranges that consume fossil 21 Nov 2021, 02:14
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Anandanwar
I am under the impression that, when ellipse is used, if both the comparisons that come out of the original statement are logically possible, then the comparison should be considered ambiguous and the usage of Ellipse is wrong. Is my understanding correct?
Hi Anandanwar,

My reply is not specific to this question, but ambiguity is never an absolute error.
Show more


Hello,

Thanks for the reply.
But this does not solve my problem.

Ambiguity may not be an absolute error, but still: If ellipse is possible then, the choice with ellipse will be considered more concise choice. Thus the choice with ellipse should be the answer.

Please shed more light on this if possible, if we have any error that deems choice A erroneous.
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Even in this age of conservation, cooking ranges that consume fossil 21 Nov 2021, 03:31
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Anandanwar
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Anandanwar
I am under the impression that, when ellipse is used, if both the comparisons that come out of the original statement are logically possible, then the comparison should be considered ambiguous and the usage of Ellipse is wrong. Is my understanding correct?
Hi Anandanwar,

My reply is not specific to this question, but ambiguity is never an absolute error.


Hello,

Thanks for the reply.
But this does not solve my problem.

Ambiguity may not be an absolute error, but still: If ellipse is possible then, the choice with ellipse will be considered more concise choice. Thus the choice with ellipse should be the answer.

Please shed more light on this if possible, if we have any error that deems choice A erroneous.
Show more

Hello Anandanwar,

We hope this finds you well.

Having gone through the question and your query, we believe we can resolve your doubt.

Although A is more concise, Option B is clearer; Option A is somewhat ambiguous due to its use of the ellipsis in place of the verb "does". Clarity of meaning is more important on GMAT than wordiness is, so Option B is the superior answer choice despite being longer.

We hope this helps.
All the best!
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Even in this age of conservation, cooking ranges that consume fossil 21 Nov 2021, 04:29
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Anandanwar
AjiteshArun

Hi Anandanwar,

My reply is not specific to this question, but ambiguity is never an absolute error.


Hello,

Thanks for the reply.
But this does not solve my problem.

Ambiguity may not be an absolute error, but still: If ellipse is possible then, the choice with ellipse will be considered more concise choice. Thus the choice with ellipse should be the answer.

Please shed more light on this if possible, if we have any error that deems choice A erroneous.

Hello Anandanwar,

We hope this finds you well.

Having gone through the question and your query, we believe we can resolve your doubt.

Although A is more concise, Option B is clearer; Option A is somewhat ambiguous due to its use of the ellipsis in place of the verb "does". Clarity of meaning is more important on GMAT than wordiness is, so Option B is the superior answer choice despite being longer.

We hope this helps.
All the best!
Experts' Global Team
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Hello Expert's Global Team,

Thanks for your reply, but it seems you did not read whole conversation.

The ellipse usage is actually not ambiguous. Its logical in this case. Please refer to the conversation chain (https://gmatclub.com/forum/even-in-this ... l#p2907693).

When the ellipse is logical then, shouldn't ellipse be preferred?
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Even in this age of conservation, cooking ranges that consume fossil 04 Dec 2021, 22:42
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Anandanwar
Hello,

Thanks for the reply.
But this does not solve my problem.

Ambiguity may not be an absolute error, but still: If ellipse is possible then, the choice with ellipse will be considered more concise choice. Thus the choice with ellipse should be the answer.

Please shed more light on this if possible, if we have any error that deems choice A erroneous.
Show more
Hi Anandanwar,

We should not make the following assumption:
Anandanwar
but still: If ellipse is possible then, the choice with ellipse will be considered more concise choice. Thus the choice with ellipse should be the answer.
Show more
Concision sometimes leads to meaning clarity issues, so it's not a good idea to create an absolute rule here. In fact, I normally ask my students to prioritise meaning clarity issues (over things like ambiguity, redundancy, and awkwardness). But just to be clear, no yes/no rule.
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Even in this age of conservation, cooking ranges that consume fossil 01 Apr 2022, 02:42
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I have a doubt in Option B. I understand that ''does'' should refer to verb ''produce''. However, I don't see any original verb ''produce'' in the preceding part of the sentence? Shouldn't original verb exist in the first place for to use supporting verb ''does'' later? ''Producing'' is just an Ing-modifier, not a verb. So how this construction is correct?

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Even in this age of conservation, cooking ranges that consume fossil 01 Apr 2022, 03:03
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VIGHNESHKAMATH
I have a doubt in Option B. I understand that ''does'' should refer to verb ''produce''. However, I don't see any original verb ''produce'' in the preceding part of the sentence? Shouldn't original verb exist in the first place for to use supporting verb ''does'' later? ''Producing'' is just an Ing-modifier, not a verb. So how this construction is correct?
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DOES need not always refer to a finite verb. DOES can refer to a ING-type modifier.

See these examples:

He wins tournaments by working harder than anyone else does.
- Here DOES refers to WORKING. The sentence is the same as this next one.
He wins tournaments by working harder than anyone else works.

The cheetah hunts by running faster than its prey does.
- Here DOES refers to RUNNING.

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Even in this age of conservation, cooking ranges that consume fossil 15 Apr 2022, 20:11
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Understanding – The sentence presents that idea that cooking ranges that consume fossil fuels are more common than cooking ranges that rely on magnetic resonance which are more efficient(how are they efficient? they produce heat more efficiently than cooking ranges that rely on natural gas)

Doubt – I am unable to understand the 2nd comparison structure for efficiency because of which i am finding all options incorrect. In all options(even correct option B) we are comparing cooking ranges with natural gas however we should compare the 2 types of cooking ranges. For example, In correct option B, producing heat more efficiently refers to cooking ranges that rely on magnetic resonance and it is compared with natural gas.
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Even in this age of conservation, cooking ranges that consume fossil 19 Jun 2022, 21:15
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Any choice with 'Which" in it is wrong because it refers to magnetic resonance and it's not magnetic resonance that produces heat. cooking ranges can produce heat in this context, not magnetic resonance.
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Hi GMATGuruNY RonTargetTestPrep AjiteshArun EducationAisle DmitryFarber GMATNinja GMATNinjaTwo AjiteshArun AnthonyRitz

When it comes to (D) - Why are we all assuming the (which clause) has to modify the closest noun only ?

Noun modifers CAN JUMP over verbs

Here are official examples

Quote:

Source : OG Question
Link here

In the OA - the "THAT CLAUSE" is jumping over the verb.

OA - B

New data from United States Forest Service ecologists show that for every dollar spent on controlled small-scale burning, forest thinning, and the training of fire-management personnel, seven dollars are saved that would have been spent on extinguishing big fires.

The relative clause in blue per my understanding is JUMPING over the verb "are saved".

The blue is referring to "Seven dollars"
Show more

Also

Quote:
Source : Manhattan SC Guide

Correct : A new CEO has been hired who will transform the company by decentralizing authority to various division heads while increasing their accountability through the use of public scorecards.

Here the (Who relative clause) is jumping over the verb "has been hired"

The (Who relative clause) is referring to the subject (CEO)

This is marked correct in the Manhattan SC guide.
Show more


In this case too - option (d) - i thought the (which clause) was jumping over the verb (Rely).

The (Which clause) is referring to the closest PLURAL noun - THOSE

One could argue - there is another plural noun closer - i.e. THAT, subject of THAT rely on magnetic resonance, because THAT (albeit singular in nature) can refer to plural subjects when THAT is the subject of the relative clause (that rely on magnetic resonance)
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Even in this age of conservation, cooking ranges that consume fossil 16 Sep 2022, 20:45
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Hi GMATGuruNY RonTargetTestPrep AjiteshArun EducationAisle DmitryFarber GMATNinja GMATNinjaTwo AjiteshArun AnthonyRitz

When it comes to (D) - Why are we all assuming the (which clause) has to modify the closest noun only ?

Noun modifers CAN JUMP over verbs

Here are official examples

Quote:

Source : OG Question
Link here

In the OA - the "THAT CLAUSE" is jumping over the verb.

OA - B

New data from United States Forest Service ecologists show that for every dollar spent on controlled small-scale burning, forest thinning, and the training of fire-management personnel, seven dollars are saved that would have been spent on extinguishing big fires.

The relative clause in blue per my understanding is JUMPING over the verb "are saved".

The blue is referring to "Seven dollars"

Also

Quote:
Source : Manhattan SC Guide

Correct : A new CEO has been hired who will transform the company by decentralizing authority to various division heads while increasing their accountability through the use of public scorecards.

Here the (Who relative clause) is jumping over the verb "has been hired"

The (Who relative clause) is referring to the subject (CEO)

This is marked correct in the Manhattan SC guide.


In this case too - option (d) - i thought the (which clause) was jumping over the verb (Rely).

The (Which clause) is referring to the closest PLURAL noun - THOSE

One could argue - there is another plural noun closer - i.e. THAT, subject of THAT rely on magnetic resonance, because THAT (albeit singular in nature) can refer to plural subjects when THAT is the subject of the relative clause (that rely on magnetic resonance)
Show more

The rule as I understand and teach it for relative pronouns is as follows:

A relative pronoun almost always has to modify the closest noun of the right type. So "who" will modify the closest person; "where" will modify the closest place; and so forth.

Relative pronouns are agreement-neutral -- neither singular nor plural (or perhaps both singular and plural would be a better way to say it). So you have to look at the verb of the relative clause to figure out how to treat them for agreement purposes.

"which produce" is going to modify the closest plural object. That's the pronoun "those," which stands for "cooking ranges." ("magnetic resonance" is singular and thus is not an option here due to "produce.") The problem is that, as a result, answer D is saying "[cooking ranges] produce heat more efficiently than natural gas does." This is a faulty comparison; we want to compare "magnetic resonance" to "natural gas" or else "cooking ranges that consume fossil fuels" to "cooking ranges that rely on magnetic resonance" -- not "cooking ranges" to "natural gas." Mind you, B isn't a great answer either. In general, a participle phrase ("producing...") at the end of a clause and set off by a comma will not modify what it's next to. But the best we can do here is to assume that B is an exception to that general rule and "producing" describes "magnetic resonance." I'll pick B on that basis, even though I'll hate doing it.

More broadly, I want to advise you to always take really, really old official questions with a grain of salt. GMAC changed vendors for Sentence Correction a dozen or so years ago, IIRC, and anything older than that is not guaranteed to be a good question by modern GMAT standards. GMAT Paper Tests are generally even far older. Like the 1990s, or even the 1980s -- back when dinosaurs still roamed the earth. Don't get too caught up in questions like these!

Oh, as for your example sentences...

Quote:
New data from United States Forest Service ecologists show that for every dollar spent on controlled small-scale burning, forest thinning, and the training of fire-management personnel, seven dollars are saved that would have been spent on extinguishing big fires.
Show more

The highlighted "that" correctly modifies the closest object, "seven dollars"; I see no difficulty here. This follows the general rule.

Quote:
Correct : A new CEO has been hired who will transform the company by decentralizing authority to various division heads while increasing their accountability through the use of public scorecards.
Show more

The highlighted "who" correctly modifies the closest person, "a new CEO"; I see no difficulty here. This follows the general rule.

I will agree that we don't prefer to have relative pronouns jump over verbs, but I don't think that's a hard-and-fast rule.

One other distinction, though, is that in your example sentences there is no noun after the verb and before the relative clause. But in the question at hand, the noun after the verb makes the situation more problematic. So perhaps that's another reason not to like answer D in this case.
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Even in this age of conservation, cooking ranges that consume fossil 23 Nov 2022, 00:50
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Dear Friends,

Here is a detailed explanation to this question-
sachinrelan
Even in this age of conservation, cooking ranges that consume fossil fuels are far more common than those that rely on magnetic resonance, producing heat more efficiently than natural gas.


(A) producing heat more efficiently than natural gas

(B) producing heat more efficiently than natural gas does

(C) which produce heat more efficiently than natural gas

(D) which produce heat more efficiently than natural gas does

(E) much more efficient at producing heat than natural gas

Show more

Meaning is crucial to solving this problem:
Understanding the intended meaning is key to solving this question; the intended meaning of the crucial part of this sentence is that cooking ranges that rely on magnetic resonance produce heat more efficiently than natural gas does, as a result.

Concepts tested here: Meaning + Modifiers + Comparisons

• Comparisons can only be made between similar things.
• The introduction of the present participle ("verb+ing"- “producing” in this case) after comma generally leads to a cause-effect relationship.

A:
1/ This answer choice incorrectly compares the action "producing heat" to the noun "natural gas"; remember, comparisons can only be made between similar things.

B: Correct.
1/ This answer choice uses the phrase "producing heat more efficiently"; the use of the "comma + present participle ("verb+ing" - "producing in this case") conveys the intended meaning - that cooking ranges that rely on magnetic resonance produce heat more efficiently than natural gas does, as a result of relying on magnetic resonance; remember, the introduction of the present participle ("verb+ing"- “producing” in this case) after comma generally leads to a cause-effect relationship.
2/ Option B correctly compares the action "producing heat" with the action "natural gas does (produce heat)".

C:
1/ This answer choice alters the meaning of the sentence through the phrase "which produce"; the use of the "which" phrase to modify "those that rely on magnetic resonance" incompletely implies that cooking ranges that rely on magnetic resonance produce heat more efficiently than natural gas does; the intended meaning is that cooking ranges that rely on magnetic resonance produce heat more efficiently than natural gas does, as a result of relying on magnetic resonance.
2/ Option C incorrectly compares the action "produce heat" to the noun "natural gas"; remember, comparisons can only be made between similar things.

D:
1/ This answer choice alters the meaning of the sentence through the phrase "which produce"; the use of the "which" phrase to modify "those that rely on magnetic resonance" incompletely implies that cooking ranges that rely on magnetic resonance produce heat more efficiently than natural gas does; the intended meaning is that cooking ranges that rely on magnetic resonance produce heat more efficiently than natural gas does, as a result of relying on magnetic resonance.

E:
1/ This answer choice alters the meaning of the sentence through the phrase "much more efficient..."; the use of this phrase to modify "those that rely on magnetic resonance" incompletely implies that cooking ranges that rely on magnetic resonance produce heat more efficiently than natural gas does; the intended meaning is that cooking ranges that rely on magnetic resonance produce heat more efficiently than natural gas does, as a result of relying on magnetic resonance.
2/ Option E incorrectly compares the action "producing heat" to the noun "natural gas"; remember, comparisons can only be made between similar things.

Hence, B is the best answer choice.

To understand the concept of "Comma Plus Present Participle for Cause-Effect Relationship" on GMAT, you may want to watch the following video (~2 minutes):



All the best!
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Even in this age of conservation, cooking ranges that consume fossil 09 Jul 2023, 12:30
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AnthonyRitz

In option B: In the second comparison, is intended comparison between "efficiency of heat produced by cooking ranges that rely on MR" and "efficiency of heat produced by natural gas"?

Also, shouldn't the comparison be between "efficiency of heat produced by cooking ranges that rely on MR" and "efficiency of heat produced by cooking ranges that rely on natural gas"?
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Even in this age of conservation, cooking ranges that consume fossil 09 Jul 2023, 12:47
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AnthonyRitz

In option B: In the second comparison, is intended comparison between "efficiency of heat produced by cooking ranges that rely on MR" and "efficiency of heat produced by natural gas"?

Also, shouldn't the comparison be between "efficiency of heat produced by cooking ranges that rely on MR" and "efficiency of heat produced by cooking ranges that rely on natural gas"?
Show more

I don't think so. Here's what I said above, about answer B:

Quote:
Mind you, B isn't a great answer either. In general, a participle phrase ("producing...") at the end of a clause and set off by a comma will not modify what it's next to. But the best we can do here is to assume that B is an exception to that general rule and "producing" describes "magnetic resonance." I'll pick B on that basis, even though I'll hate doing it.
Show more

The idea would be that the comparison is between "magnetic resonance" and "natural gas."

It would be awesome if this question could compare
Quote:
"efficiency of heat produced by cooking ranges that rely on MR" and "efficiency of heat produced by cooking ranges that rely on natural gas"?
Show more
... if any answer gave us that option. Sadly, it's not to be. We have to make the best of the choices we're given.

In that vein, I also said this:

Quote:
More broadly, I want to advise you to always take really, really old official questions with a grain of salt. GMAC changed vendors for Sentence Correction a dozen or so years ago, IIRC, and anything older than that is not guaranteed to be a good question by modern GMAT standards. GMAT Paper Tests are generally even far older. Like the 1990s, or even the 1980s -- back when dinosaurs still roamed the earth. Don't get too caught up in questions like these!
Show more
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Even in this age of conservation, cooking ranges that consume fossil 04 Oct 2023, 18:27
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in A the issue is that the meaning changes
intended meaning is : cooking ranges generate more heat than what natural gas produces
conveyed meaning is : cooking ranges generate more heat than cooking ranges generate natural gas
Answer is B
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Even in this age of conservation, cooking ranges that consume fossil 03 Nov 2023, 14:12
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Even in this age of conservation, cooking ranges that consume fossil fuels are far more common than those that rely on magnetic resonance, producing heat more efficiently than natural gas.

Apologies if I hurt anyone's feelings about this question, but option B is not good. Having said rest 4 are incorrect as well for obvious reasons. Why did I say B is incorrect? Comma + ING is an adverbial that needs to refer to the verb. The verb here is "rely" (those that - if we unpack it - cooking ranges rely....). The possible way it can work is if we say like this: "Cooking ranges (those refers to cooking ranges) that rely on magnetic resonance produce heat more efficiently than "the cooking ranges that rely" on natural gas produce ("does" refers back to the verb produce). Again, it's not ideal, but I couldn't think better than this. Experts can pitch in. If you get stuck on this question, don't boil your blood, as there are issues. Had there been no comma without producing, this would have been perfect. But with the comma, it's not, and with all due respect to official questions, if I have to come up with something, this is the best I can. :(

Let's now eliminate others -

(A) producing heat more efficiently than natural gas - ING + comma refers to "cooking ranges rely." Here, the act of "production" is compared with "natural gas" - wrong.

(B) producing heat more efficiently than natural gas does - as we discussed above.

(C) which produce heat more efficiently than natural gas - "which" refers to magnetic resonance, which is singular, so "produce" a plural verb is wrong. Moreover, the act of production is compared with natural gas - wrong.

(D) which produce heat more efficiently than natural gas does - while "does" is good, which issues stay.

(E) much more efficient at producing heat than natural gas - comparing the act of producing heat with natural gas. Wrong
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