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Air traffic routes over the North Pole are currently used by only two

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TargetMBA007

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26 Nov 2020, 23:01

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MyGuruStefan

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When dealing with fully underlined sentences such as this, try to identify a single error first to streamline the elimination process for maximum efficiency. In the sentence as written, the pronoun "it" is ambiguous because it lacks a clear antecedent. Eliminate A and look for any choices that also include ambiguous pronouns. Choices B and C also include the ambiguous or otherwise erroneous pronouns "it" and "which" that do not correctly and clearly refer to a prior subject. Eliminate B and C as well for their pronoun errors.

Choice D properly orders the information in the sentence and eliminates the ambiguous pronouns. Choice E eliminates the main predicate phrasing of the sentence by omitting "are" and leaves it without a clear subject-verb pairing. It also includes the incorrect idiom "found... as", which should be "found... to be". Eliminate choice E. The correct answer is D.

MyGuruStefan Thanks for that wonderful explanation.
The use of the pronoun "It" is an interesting one here. As per Magoosh - https://magoosh.com/gmat/verbal/sentenc ... orrection/

• The empty IT, does NOT need to have an antecedent, unlike the other pronouns.
• The “empty it” is an “it” that appears at the beginning of a sentence or clause: this pronoun has no simple noun antecedent. The “empty it” often serves to make sentences more indirect and wordy, so usually they are not correct on the GMAT. For example:

4a) It is more expensive to dine out every night than to prepare one's own meals at home.
4b)
Dining out every night is more expensive than preparing one's own meals at home.

The first sentence is 100% grammatically correct, but it is wordy and indirect; the second is much more concise and powerful. That’s an example of an “empty it” making a sentence wordier and rhetorically weaker. This is most often the case, but in rare cases, the “empty it” is perfectly acceptable.

This makes me wonder, if IT is wrong here, due to an antecedent error or simply because it makes the sentence wordy?

The "it" is incorrect, not merely wordy, because the antecedent should be the closest immediately preceding or following possible singular noun, which would be either "day" or "study" neither of which would logically make sense in context. Therefore, this would not qualify as the so-called "empty it". I hope this clarifies your issue. ~Stefan

Thanks Stefan, but my understanding is when we are looking at a placeholder IT, we dont need to chase down its antecedents, as the idea is, it is acting as a placeholder and hence would have no antecedents. Are there any specific rules that helps us differentiate when the placeholder IT (without antecedents) can work and not work?

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TargetMBA007

The empty it must not have possible antecedents to which it could refer. Hence, why the empty it cannot be applied here as there are possible referents nearby to it that would be illogical. Honestly, the GMAT is so careful in applying the empty it that is your test to if the empty it is being used as there will be no possible referents in proximity. Hope that helps. ~Stefan

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AbdurRakib

The Official Guide for GMAT Review 2018
Practice Question
Sentence Correction
Question No.: 674

Air traffic routes over the North Pole are currently used by only two or three planes a day, but it was found by a joint Canadian–Russian study to be both feasible as well as desirable if those routes are opened to thousands more commercial planes a year.

A. Air traffic routes over the North Pole are currently used by only two or three planes a day, but it was found by a joint Canadian–Russian study to be both feasible as well as desirable if those routes are opened to thousands more commercial planes a year.

B. Currently used by only two or three planes a day, a joint Canadian–Russian study has found that if air traffic routes over the North Pole are opened to thousands more commercial planes a year, it would be both feasible and desirable.

C. A joint Canadian–Russian study, finding it to be both feasible as well as desirable to open air traffic routes over the North Pole, which are currently used by only two or three planes a day, to thousands more commercial planes a year.

D. Although air traffic routes over the North Pole are currently used by only two or three planes a day, a joint Canadian–Russian study has found that opening those routes to thousands more commercial planes a year is both feasible and desirable.

E. With air traffic routes over the North Pole currently used by only two or three planes a day, opening those routes to thousands more commercial planes a year has been found by a joint Canadian—Russian study as both feasible and desirable

This question is based on Modifiers and Idiomatic Usage.

The sentence contains the correlative conjunctions ‘both-and’. The conjunction ‘both’ cannot be paired with the phrase ‘as well as’. On that basis, we can rule out options A and C.

Option B contains a modifier error; the noun “a joint Canadian–Russian study” is placed after the modifier “Currently used by only two or three planes a day”, implying that the study is currently used only by two or three planes a day. Since the meaning conveyed is illogical, Option B can be ruled out.

Option E contains an idiomatic usage error – “found by….as”. The verb ‘found’ should be followed by the infinitive ‘to be’.
Furthermore, this option is in the passive voice, making the sentence longer and wordier.
The preposition ‘with’ also changes the meaning. There is a slight contradictory idea implied in the sentence. The use of the preposition 'with' conveys a reason and not contradiction. So, Option E can be eliminated.

Option D uses the word ‘although’ to convey the contradiction.
This option is also in the active voice, so it is clearer and more concise.
The option also contains the appropriate pair of correlative conjunctions – both-and.
Therefore, D is the most appropriate option.

Jayanthi Kumar.

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EducationAisle

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In my opinion, COMMA + WHICH is correctly placed here and refers back to "air traffic routes" AND NOT "the North Pole" because "the North Pole" is the object of preposition "over the North Pole" and therefore, is not the closest preceding main noun.

Please tell me whether I am right or wrong.

Hi , which can refer to object of preposition. There are numerous such official questions. For example:

The commission proposed that funding for development of the park, which could be open to the public early next year, be obtained through a local bond issue.

Here, which refers to park (park is the object of preposition of in this example).

However, in the sentence under consideration, which cannot modify North Pole because the sentence says which are. So, which can only modify a plural Noun in this sentence.

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

I'm sorry, I am not sure about that. In my perception 'which' refers back to air traffic routes correctly. Whatever follows the preposition is part of the prepositional phrase, which modifies the previous noun. Now, 'which' refers back to the last noun, hence, the noun 'routes' ('air traffic' would be the compound adjective). Manhattan Prep has some good material on this.

Likewise in your example, 'of the park' is a prepositional phrase, as also is 'for development'. The reason your example is correct is that 'which' refers back to the noun 'funding' which could be 'open to the public early next year' as well.

At least this is how I see it.

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SebastianN

Likewise in your example, 'of the park' is a prepositional phrase, as also is 'for development'. The reason your example is correct is that 'which' refers back to the noun 'funding' which could be 'open to the public early next year' as well.

At least this is how I see it.

This interpretation is not correct.

This sentence is from The Official Guide for GMAT Verbal Review 2016.

Official explanation (from GMAT official guide): In this sentence, which clearly modifies park.

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EducationAisle

SebastianN

Ok, you are probably right. I don't understand the logic though. In my perception the GMAC applies the same rules always on every topic, regardkless of the question. The rule I know is that comma+'which' always refers back to the last noun before the comma.
Why does the explanation say that this option is correct compared to other answer choices? I don't have the material of 2016.

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SebastianN

In my perception the GMAC applies the same rules always on every topic, regardkless of the question. The rule I know is that comma+'which' always refers back to the last noun before the comma.

I am not understanding your question. I thought that just a couple of post back, you mentioned that which will not refer to the last noun before the comma, if that noun is a part of prepositional phrase.

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I would be careful using the presence of “it” as the sole basis for elimination of answer A and other such sentence versions that use an expletive “it” as the Subject.

This kind of “it” may be acceptable when it is “pushing back” an Infinitive Phrase or a Substantive Noun Clause to later in the sentence.

In this sentence, the expletive “it” is indeed problematic but it may not always be the case.

Awkward Ex: “To study hard for the exam is crucial.”

—-Awkward, but not necessarily grammatically incorrect)

Better ex: “It is crucial to study hard for the exam.”

Awkward ex: “That he will get a high score on the exam is certain.”

—— awkward but not necessarily grammatically incorrect

Better ex: “It is certain that he will get a high score on the exam.”

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Fdambro294

All good points, although in this sentence the "it" clearly isn't expletive as the word is used in the referential form. Hooray for the ambiguities of English, though. Keep up the good GMAT verbal practice! ~Stefan

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Air traffic routes over the North Pole are currently used by only two or three planes a day, but it was found by a joint Canadian–Russian study to be both feasible as well as desirable if those routes are opened to thousands more commercial planes a year.

1.
1-1
S find O to be OC
I find the book interesting.
*
S+find+O (to be)
Russian study has found opening those routes to thousands more commercial planes a year to be both feasible and desirable. (E)
Russian study has found if those routes are opened to thousands more commercial planes a year to be both feasible and desirable.。

1-2
O is found by S to be OC/O is found to be OC by S
the book is found by me to be interesting.
the book is found to be interesting by me .
*
Opening those routes to thousands more commercial planes a year is found by Russian study to be both feasible and desirable.
Opening those routes to thousands more commercial planes a year is found to be both feasible and desirable by Russian study.

1-3
S find it to be OC O
I find it to be interesting the book
*
S+find+it (to be) OC O
Russian study has found it to be both feasible and desirable to open those routes to thousands more commercial planes a year. (C)
Russian study has found it to be both feasible and desirable if those routes are opened to thousands more commercial planes a yearIf

1-4
it is found by S to be OC O/it is found to be OC O by S/
it is found by me to be interesting the book /it is found to be interesting the book by me/
*
It is found by Russian study to be both feasible and desirable if those routes are opened to thousands more commercial planes a year.(A)

1-5
S find that S+V+C
*
Although air traffic routes over the North Pole are currently used by only two or three planes a day, a joint Canadian–Russian study has found that opening those routes to thousands more commercial planes a year is both feasible and desirable.

2.
when/if/whether can both use as adj/noun clause

noun clause: used to introduce a clause, often in indirect speech, that shows two or more possibilities
adjective clause: used to say that a particular thing can or will happen only after something else happens or becomes true

A. Air traffic routes over the North Pole are currently used by only two or three planes a day, but it was found by a joint Canadian–Russian study to be both feasible as well as desirable if those routes are opened to thousands more commercial planes a year.
a-1
we can not use it for the whole thing(Air traffic routes over the North Pole are currently used by only two or three planes a day)
a-2
and we can not use it for expletive because:
"if" in this sentence means adjective clause: used to say that a particular thing can or will happen only after something else happens or becomes true
it for expletive+ tov/noun clause.
a-3
both feasible as well as desirable

B. Currently used by only two or three planes a day, a joint Canadian–Russian study has found that if air traffic routes over the North Pole are opened to thousands more commercial planes a year, it would be both feasible and desirable.
if-adv clause.

b-1
if S are..., it would be...
it(wrong) can not mean the whole sentence: air traffic routes over the North Pole are opened to thousands more commercial planes a year
would be(wrong)
if air traffic routes over the North Pole are opened to thousands more commercial planes a year, it is/will both feasible and desirable.
b-2
Currently used by only two or three planes a day, a joint Canadian–Russian study

C. A joint Canadian–Russian study, finding it to be both feasible as well as desirable to open air traffic routes over the North Pole, which are currently used by only two or three planes a day, to thousands more commercial planes a year.
c-1
S+V+O
c-2
both feasible as well as desirable

D. Although air traffic routes over the North Pole are currently used by only two or three planes a day, a joint Canadian–Russian study has found that opening those routes to thousands more commercial planes a year is both feasible and desirable.(OA)

E. With air traffic routes over the North Pole currently used by only two or three planes a day, opening those routes to thousands more commercial planes a year has been found by a joint Canadian—Russian study as both feasible and desirable
opening those routes to thousands more commercial planes a year has been found by a joint Canadian—Russian study TO BE both feasible and desirable

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Air traffic routes over the North Pole are currently used by only two or three planes a day, but it was found by a joint Canadian–Russian study to be both feasible as well as desirable if those routes are opened to thousands more commercial planes a year.

A. Air traffic routes over the North Pole are currently used by only two or three planes a day, but it was found by a joint Canadian–Russian study to be both feasible as well as desirable if those routes are opened to thousands more commercial planes a year.

B. Currently used by only two or three planes a day, a joint Canadian–Russian study has found that if air traffic routes over the North Pole are opened to thousands more commercial planes a year, it would be both feasible and desirable.

C. A joint Canadian–Russian study, finding it to be both feasible as well as desirable to open air traffic routes over the North Pole, which are currently used by only two or three planes a day, to thousands more commercial planes a year.

D. Although air traffic routes over the North Pole are currently used by only two or three planes a day, a joint Canadian–Russian study has found that opening those routes to thousands more commercial planes a year is both feasible and desirable.

E. With air traffic routes over the North Pole currently used by only two or three planes a day, opening those routes to thousands more commercial planes a year has been found by a joint Canadian—Russian study as both feasible and desirable

GMATNinja MartyTargetTestPrep KarishmaB AndrewN

"currently used by" - use of currently means that it should be present continuous tense as the action is continuing in present time - why used is correct here - this makes it present perfect

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AbdurRakib

Air traffic routes over the North Pole are currently used by only two or three planes a day, but it was found by a joint Canadian–Russian study to be both feasible as well as desirable if those routes are opened to thousands more commercial planes a year.

A. Air traffic routes over the North Pole are currently used by only two or three planes a day, but it was found by a joint Canadian–Russian study to be both feasible as well as desirable if those routes are opened to thousands more commercial planes a year.

B. Currently used by only two or three planes a day, a joint Canadian–Russian study has found that if air traffic routes over the North Pole are opened to thousands more commercial planes a year, it would be both feasible and desirable.

C. A joint Canadian–Russian study, finding it to be both feasible as well as desirable to open air traffic routes over the North Pole, which are currently used by only two or three planes a day, to thousands more commercial planes a year.

D. Although air traffic routes over the North Pole are currently used by only two or three planes a day, a joint Canadian–Russian study has found that opening those routes to thousands more commercial planes a year is both feasible and desirable.

E. With air traffic routes over the North Pole currently used by only two or three planes a day, opening those routes to thousands more commercial planes a year has been found by a joint Canadian—Russian study as both feasible and desirable

They have not switched the tense. It is a passive construction.

Only 2-3 planes use the routes over NP.
Routes over NP are used by only 2-3 planes.
Present tense is shown by the use of 'are.'

Active - A does B.
Passive - B is done by A.

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Air traffic routes over the North Pole are currently used by only two or three planes a day, but it was found by a joint Canadian–Russian study to be both feasible as well as desirable if those routes are opened to thousands more commercial planes a year.

A. Air traffic routes over the North Pole are currently used by only two or three planes a day, but it was found by a joint Canadian–Russian study to be both feasible as well as desirable if those routes are opened to thousands more commercial planes a year.
it-has no singular referent, both-as well as is incorrect

B. Currently used by only two or three planes a day, a joint Canadian–Russian study has found that if air traffic routes over the North Pole are opened to thousands more commercial planes a year, it would be both feasible and desirable.
The starting modifier is modifying the study, which is incorrect

C. A joint Canadian–Russian study, finding it to be both feasible as well as desirable to open air traffic routes over the North Pole, which are currently used by only two or three planes a day, to thousands more commercial planes a year.
Both-as well as is incorrect, it-has no singular referent

D. Although air traffic routes over the North Pole are currently used by only two or three planes a day, a joint Canadian–Russian study has found that opening those routes to thousands more commercial planes a year is both feasible and desirable.-Correct

E. With air traffic routes over the North Pole currently used by only two or three planes a day, opening those routes to thousands more commercial planes a year has been found by a joint Canadian—Russian study as both feasible and desirable
opening has been found by a joint Canadian—Russian study - incorrect structure & meaning

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