El Niño, the periodic abnormal warming of the sea surface off Peru, a

Question

El Niño, the periodic abnormal warming of the sea surface off Peru,  a phenomenon in which changes in the ocean and atmosphere combine allowing the warm water that has accumulated  in the western Pacific to flow back to the east.

(A) a phenomenon in which changes in the ocean and atmosphere combine allowing the warm water that has accumulated

(B) a phenomenon where changes in the ocean and atmosphere are combining to allow the warm water that is accumulating

(C) a phenomenon in which ocean and atmosphere changes combine and which allows the warm water that is accumulated

(D) is a phenomenon in which changes in the ocean and atmosphere combine to allow the warm water that has accumulated

(E) is a phenomenon where ocean and atmosphere changes are combining and allow the warm water accumulating

OG16 SC109

whamberto · Accepted Answer

I have chosen D for this question:

A. Sentence is a fragment because it lacks a main verb. Currently, the sentence has 2 modifiers for El Nino - the 2nd modifier is therefore misplaced at the moment.

B. Sentence is a fragment because it lacks a main verb.

C. Again, the sentence is a fragment.

D. This sentence is correct. The use of present perfect tense is fine because it is describing how water accumulated in the past and continues to accumulate in the present will flow back East.

E. The use of "where" to describe phenomenon is incorrect because "where" is used to describe places, not events. Also, "are combining" is really confusing. If this is correct, then we a have a parallelism error because "are combining" is not parallel to "allow."

Zarrolou · Answer

C has an incorrect structure: if you eliminate the modifer  " the periodic abnormal warming of the sea surface off Peru"  you'll see that the word " is " must be present

El Nino,      ,  a phenomenon in which ocean and atmosphere changes combine and which allows the warm water that is accumulated  in the western Pacific to flow back to the east.

C looks like this:  El Nino a phenomenon in which  . There is something missing... like a verb...

Hope it's clear

ExpertsGlobal5 · Answer

Dear Friends,

Here is a detailed explanation to this question-

Concepts tested here: Tenses + Grammatical Construction + Pronouns + Verb Forms

• The simple present tense is used to indicate actions taking place in the current time frame, indicate habitual actions, state universal truths, and convey information that is permanent in nature. 
• The simple present continuous tense is used to refer to actions that are currently ongoing and continuous in nature.
• The present perfect tense (marked by the use of "has/have") is used to refer to actions that concluded in the past but continue to affect the present.
• "where" can only be used to refer to physical locations.
• For referring to the intent/purpose of an action, the infinitive verb form ("to + base form of verb" - "to + allow" in this sentence) is preferred over the present participle ("verb+ing" - "allowing" in this sentence).

A:  This answer choice fails to form a complete sentence; as "combine" and "has accumulated" are both parts of a modifying phrase, there is no active verb to act upon the subject noun "El Niño". Further, Option A uses the present participle ("verb+ing" - "allowing" in this sentence) to refer to the purpose of the action "combine"; remember, for referring to the intent/purpose of an action, the infinitive verb form ("to + base form of verb") is preferred over the present participle.

B:  This answer choice fails to form a complete sentence; as "are combining" and "is accumulating" are both parts of a modifying phrase, there is no active verb to act upon the subject noun "El Niño". Further, Option B incorrectly refers to the noun "phenomenon" with the pronoun "where"; remember, "where" can only be used to refer to physical locations. Additionally, Option B incorrectly uses the simple present continuous tense verb "are combining" to refer to a statement of universal fact; remember, statements of universal fact are best conveyed through the simple present tense, and the simple present continuous tense is used to refer to actions that are currently ongoing and continuous in nature. Besides, Option B incorrectly uses the simple present continuous tense verb "is accumulating" to refer to an action that concluded in the past but continues to affect the present; please remember, the present perfect tense (marked by the use of "has/have") is used to refer to actions that concluded in the past but continue to affect the present, and the simple present continuous tense is used to refer to actions that are currently ongoing and continuous in nature.

C:  This answer choice fails to form a complete sentence; as "combine" and "is accumulated" are both parts of a modifying phrase, there is no active verb to act upon the subject noun "El Niño". Further, Option C incorrectly uses the simple present tense verb "is accumulated" to refer to an action that concluded in the past but continues to affect the present; please remember, the present perfect tense (marked by the use of "has/have") is used to refer to actions that concluded in the past but continue to affect the present, and the simple present tense is used to indicate actions taking place in the current time frame, indicate habitual actions, state universal truths, and convey information that is permanent in nature.

D:   Correct.  This answer choice acts upon the independent subject noun "El Niño" with the active verb "is" to form a complete thought, producing a complete sentence. Further, Option D avoids the pronoun error seen in Options B and E, as it uses the phrase "in which" rather than "where". Additionally, Option D correctly uses the simple present tense verb "combine" to refer to a statement of universal fact. Moreover, Option D correctly uses the present perfect tense verb "has accumulated" to refer to an action that concluded in the past but continues to affect the present. Besides, Option D uses the infinitive verb form ("to + base form of verb" - "to + allow" in this sentence) to refer to the purpose of the action "combine".

E:  This answer choice incorrectly refers to the noun "phenomenon" with the pronoun "where"; remember, "where" can only be used to refer to physical locations. Further, Option E uses the simple present continuous tense verb "are combining" to refer to a statement of universal fact; remember, statements of universal fact are best conveyed through the simple present tense, and the simple present continuous tense is used to refer to actions that are currently ongoing and continuous in nature. Additionally, Option E incorrectly uses the present participle ("verb+ing" - "accumulating" in this sentence) to refer to an action that concluded in the past but continues to affect the present; please remember, the present perfect tense (marked by the use of "has/have") is used to refer to actions that concluded in the past but continue to affect the present.

Hence, D is the best answer choice.

To understand the concept of "Simple Tenses" on GMAT, you may want to watch the following video (~2 minutes):

https://www.youtube.com/watch?v=ATNTtugB9fM

To understand the concept of "Present Perfect Tense" on GMAT, you may want to watch the following video (~1 minute):

https://www.youtube.com/watch?v=kNmT9obXukI

To understand the concept of "Simple Continuous Tenses" on GMAT, you may want to watch the following video (~1 minute):

https://www.youtube.com/watch?v=Fndw1N0nWXw

To understand the concept of "Infinitives" versus "Present Participle" on GMAT, you may want to watch the following video (~1 minute):

https://www.youtube.com/watch?v=qbr_XRGL3js

All the best!
Experts' Global Team

believe2 · Answer

would go with D

I may not explain it very well but here is what I think:
a,b c do not have a verb to complete the clause that began with El Nino, however d & e have  IS  that is completing the clause. The 'IN WHICH' in d is better than 'where' in E. also E sounds odd otherwise.

MHIKER · Answer

Why is  has  used in the correct choice D?

fozzzy · Answer

Can someone explain the Error in Option C... I know its wrong but can't figure out what it is. Thanks in advance!

targetdec31 · Answer

Any one about usage of  HAS  in D?

EducationAisle · Answer

has accumulated  is a  present perfect  tense, and is primarily used to depict an event that has happened at some unspecific time before the current time.

Perhaps this can be best understood by few examples:

Now a days, the new Governments always rollback the changes that have been implemented by the old Governments. 
- The clause in present perfect ( that have been implemented by the old Governments ) is modifying  changes

Everyday, the Sun clears the mist that has been accumulated by the low temperatures of the night. 
- The clause in present perfect ( that has been accumulated by the low temperatures of the night ) is modifying  mist

In El Nino, changes combine to allow the warm water that has accumulated in the western Pacific to flow back to the east. 
- The clause in present perfect ( that has accumulated in the western Pacific ) is modifying  warm water

p.s. Our book   SC Nirvana   discusses  Present Perfect  tense, its application and examples in significant detail. If you can PM you email, I can send you the corresponding section.

russ9 · Answer

Can someone explain why "combine" or "to allow" in A and B is not considered a verb?

EducationAisle · Answer

combine  in A and  are  in B are indeed verbs; but these verbs are only part of  dependent clauses ; so, there is no  independent clause  in A and B; and there cannot be a sentence  without  an  Independent  clause.

Let's take a simplified example that mirrors A:

James, a married man, an athlete who combines skill and strength enabling him to win medals.

This is not a valid sentence, because the verb  combines  only appears as a part of  dependent clause :  who combines skill and strength enabling him to win medals .

One way to fix it would be:

James, a married man, is an athlete who combines skill and strength to enable him to win medals.

Now, we have an  Independent  clause:  James is an athlete

By the way, A and B also have  back to back  modifiers ( the periodic abnormal ...  and and  a phenomenon in which.... ), modifying the same entity  El Nino . This is not GMAT's stylistic preference.

Skywalker18 · Answer

El Nino, the periodic abnormal warming of the sea surface off Peru,  a phenomenon in which changes in the ocean and atmosphere combine allowing the warm water that has accumulated  in the western Pacific to flow back to the east.

(A) a phenomenon in which changes in the ocean and atmosphere combine allowing the warm water that has accumulated -- El Nino does not have a verb ; usage of allowing is incorrect
(B) a phenomenon where changes in the ocean and atmosphere are combining to allow the warm water that is accumulating -- El Nino does not have a verb ; usage of where to refer to a phenomenon is incorrect
(C) a phenomenon in which ocean and atmosphere changes combine and which allows the warm water that is accumulated -- El Nino does not have a verb ; meaning change because of usage of and 
(D) is a phenomenon in which changes in the ocean and atmosphere combine to allow the warm water that has accumulated -- Correct
(E) is a phenomenon where ocean and atmosphere changes are combining and allow the warm water accumulating -- usage of where to refer to a phenomenon is incorrect ; present continuous are combining is incorrect

AjiteshArun  ,  daagh  ,  mikemcgarry  , GMATNinja  , egmat , other experts-- please enlighten
In the correct answer , is the usage of "to allow" correct? To allow should express intent/purpose

Answer D

AjiteshArun · Answer

To  can be used for  intent , but it has a whole lot of other uses too. In this case they're trying to get at  result . For example,

The opening was large enough to allow only a small child through.

Here the meaning is not (a)  for the purpose of allowing only a small child through the opening was large enough  but (b)  the size of the opening was such that only a particular result was possible .

EMPOWERgmatVerbal · Answer

Hi Puilunchristin,

Thank you for your question. Let's look at this question, one problem at a time, and see if we can narrow it down to the correct answer!

The first major difference between the answers is how they begin: a phenomenon vs. is a phenomenon. The problem with just using "a phenomenon" is that it creates a sentence fragment. There is no verb in the sentence - it's just a subject with two modifiers. So, let's get rid of answers A, B, & C because all three answers aren't complete sentences.

Now that we've narrowed it down to only D & E, let's look at what's different about each one:

(D) is a phenomenon  in which  changes in the ocean and atmosphere  combine  to allow the warm water  that has accumulated

Answer D is the  CORRECT  answer because it uses the phrase "in which" to indicate an explanation, not the phrase "where" which indicates place or direction. It also uses clearer verbs "combine" and "has accumulated" to show meaning.

(E) is a phenomenon  where  ocean and atmosphere changes  are combining  and allow the warm water  accumulating

Answer E is  INCORRECT  because it uses the word "where," which should only be used to show place or direction - NOT to indicate you are giving an example or explanation. The other problem is using verbs like "are combining" and "accumulating." They both tell the reader that this phenomenon is happening only RIGHT NOW, instead of saying it's something that happens in the past and could also happen in the present or future.

CrackverbalGMAT · Answer

This is an interesting question. 
If we do not read the underlined portion carefully along with the rest of the sentence, we might think that it is a modifier that should begin with ‘a phenomenon’. 
But here, there is already a modifier after El Nino.

As a result, the options without the word ‘is’ end up as sentence fragments without a verb.

We can  eliminate   Options A, B and C  for this reason.

Between  Options D  and  E , Option D uses ‘where’ to refer to ‘phenomenon’. The correct usage is ‘in which’.

Eliminate   Option E.

Option D  is the best choice.

Hope this helps!

yatharthdubey · Answer

Hi,
It would have been correct if it had 'oceanic' and 'atmospheric'.
Hope this clears it.

EducationAisle · Answer

Not really Yatharth; C does not have any  main verb . Basically, there is  no  Independent clause in C (every complete sentence must have at least one Independent clause).

So, C is (what's called) a  sentence fragment .

You can watch our  video  on  Independent and Dependent Clauses .

ar21x · Answer

A,B and C here are fragments 
E incorrectly uses when and -ing form 
 D here is the correct answer

vishnugmatgupta · Answer

"Has" is used for present perfect tense which implies that the task has been carried out over the period of time and the task is still going on or its effect is still present in the present moment.

"Has" is used because logically water has accumulated over time and it's effect is still present i.e. the accumulated warm water is still present in the western Pacific.

ashutosh_73 · Answer

Hi AjiteshArun Below are the two versions of Option A after adding the main verb ''IS''. The only difference is a comma before ''allowing'' Are the below two sentences convey the correct and same meaning? 1. El Niño, the periodic abnormal warming of the sea surface off Peru, is a phenomenon in which changes in the ocean and atmosphere combine allowing the warm water that has accumulated in the western Pacific to flow back to the east . Here in ''changes in the ocean and atmosphere combine allowing'', does ''allowing'' modify the combine correctly? Its an adverbial modifier, right? 2. El Niño, the periodic abnormal warming of the sea surface off Peru, is a phenomenon in which changes in the ocean and atmosphere combine ,allowing the warm water that has accumulated in the western Pacific to flow back to the east . Thanks

El Niño, the periodic abnormal warming of the sea surface off Peru, a

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GMAT Sentence Correction (SC - EA only) Questions

El Niño, the periodic abnormal warming of the sea surface off Peru, a

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

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