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555-605 Level|   Modifiers|   Parallelism|   Subject Verb Agreement|                  
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The peaks of a mountain range, acting like rocks in a streambed, produ 19 Nov 2021, 05:37
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wps002
Hi Everyone. I have a doubt here. How can "them" in Option C refer to two different antecedents and be perfectly okay to be the correct answer? Is it okay to have same pronouns to have two different (but logical) antecedents? (Unlike what explicitly cited on Manhattan GMAT guide) Or is it okay because both the ICs are separated here by a semi-colon. I genuinely confused. Thanks.

Hello wps002,

We hope this finds you well.

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

Here, "them" does not refer to "crests" and "troughs" independently, rather, "them" refers to the combined noun phrase "crests and troughs"; thus, "them" has only one antecedent. Remember, two nouns joined by "and" form a single, plural noun phrase.

To understand the concept of "And" versus Other Conjunctions on GMAT, you may want to watch the following video (~1 minute):



All the best!
Experts' Global Team
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Hey, I think I wasn't clear enough with my doubt.
The peaks of a mountain range, acting like rocks in a streambed, produce ripples in the air flowing over them; the resulting flow pattern, with crests and troughs that remain stationary although the air that forms them is moving rapidly, is known as "standing waves".

These two thems have different antecedents.
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The peaks of a mountain range, acting like rocks in a streambed, produ 19 Nov 2021, 08:22
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Hi Everyone. I have a doubt here. How can "them" in Option C refer to two different antecedents and be perfectly okay to be the correct answer? Is it okay to have same pronouns to have two different (but logical) antecedents? (Unlike what explicitly cited on Manhattan GMAT guide) Or is it okay because both the ICs are separated here by a semi-colon. I genuinely confused. Thanks.

Hello wps002,

We hope this finds you well.

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

Here, "them" does not refer to "crests" and "troughs" independently, rather, "them" refers to the combined noun phrase "crests and troughs"; thus, "them" has only one antecedent. Remember, two nouns joined by "and" form a single, plural noun phrase.

To understand the concept of "And" versus Other Conjunctions on GMAT, you may want to watch the following video (~1 minute):



All the best!
Experts' Global Team




Hey, I think I wasn't clear enough with my doubt.
The peaks of a mountain range, acting like rocks in a streambed, produce ripples in the air flowing over them; the resulting flow pattern, with crests and troughs that remain stationary although the air that forms them is moving rapidly, is known as "standing waves".

These two thems have different antecedents.
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Hello wps002,

Thank you for the clarification.

In this case, it appears that the correct option has a pronoun error. However, since all the answer choices share this error, Option C is still the best answer choice. Remember, on the GMAT, you must look for the best of the given answer choices, not a perfect answer choice. In rare cases, all of the answer choices may be imperfect; in these cases, you must look for the one that has the least errors.

We hope this helps.
All the best!
Experts' Global Team
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The peaks of a mountain range, acting like rocks in a streambed, produ 24 Feb 2022, 02:05
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Hi ExpertsGlobal5

In C we have "crests and troughs that remain stationary although the air that forms them is moving rapidly"
using present tense implies that the air is still forming them, though acceptable from a geological stand point since as long as air blows it will give shape to structures, ı believe past tense "formed" them would be better since crest and trough are already formed
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The peaks of a mountain range, acting like rocks in a streambed, produ 24 Feb 2022, 05:47
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Hi ExpertsGlobal5

In C we have "crests and troughs that remain stationary although the air that forms them is moving rapidly"
using present tense implies that the air is still forming them, though acceptable from a geological stand point since as long as air blows it will give shape to structures, ı believe past tense "formed" them would be better since crest and trough are already formed
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Hello gloomybison,

We hope this finds you well.

To provide a bit of clarity here, the "crests and troughs" in this sentence refer to a pattern of flowing air; the intended meaning is that the peaks cause flowing air to form into a pattern of crests and troughs.

The use of the simple present tense is appropriate here because this is information (that the air forms this pattern) that is permanent in nature, not an action that concluded in the past.

We hope this helps.
All the best!
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The peaks of a mountain range, acting like rocks in a streambed, produ 07 Mar 2022, 15:56
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in option C that refers to plural crests and troughs...isn't it wrong?
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The peaks of a mountain range, acting like rocks in a streambed, produ 07 Mar 2022, 23:10
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Prachita123
in option C that refers to plural crests and troughs...isn't it wrong?
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Hi Prachita, it is exceedingly common on GMAT, for "that" to refer to entire "phrases", based on what makes logical sense.

p.s. Our book EducationAisle Sentence Correction Nirvana discusses modifier framework for "that", its application and examples in significant detail. If you or someone is interested, PM me your email-id; I can mail the corresponding section.
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The peaks of a mountain range, acting like rocks in a streambed, produ 08 Mar 2022, 06:35
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Prachita123
in option C that refers to plural crests and troughs...isn't it wrong?
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Hello Prachita123,

We hope this finds you well.

To answer your query, the use of "that" is not an error here because in this sentence, "that" serves as a preposition, rather than as a pronoun; as a preposition, "that" can refer to plural nouns.

We hope this helps.
All the best!
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The peaks of a mountain range, acting like rocks in a streambed, produ 08 Mar 2022, 07:27
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Thank you EducationAisle and ExpertsGlobal
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The peaks of a mountain range, acting like rocks in a streambed, produ 08 May 2022, 14:18
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The ”air is moving” in C threw me off in this question and thus, I ignored the parallelism error in E which I now understand. But can someone explain why “air is moving rapidly” is correct? To me it should be moves and is moving should be wrong since it is not a thing happening currently in the continuous tense.

GMATNinja any ideas on this?
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The peaks of a mountain range, acting like rocks in a streambed, produ 09 Jun 2022, 20:46
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So lets make a quick split after analyzing the sentence.

I see an extremely helpful split amongst the answer choices..... the use of IS and ARE before "standing waves" is referring to the flow patter, which is singular! Therefore, lets knock out A B and D. See the bold below for more detail.

The Pattern The peaks of a mountain range, acting like rocks in a streambed, produce ripples in the air flowing over them; the resulting flow pattern, with crests and troughs that remain stationary although the air that forms them is moving rapidly, are known as "standing waves."

Next, we can see that the awkward structure of E isnt going to fly on the GMAT as it isn't clearly stating the intended meaning of the sentence. So lets go with C!
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The peaks of a mountain range, acting like rocks in a streambed, produ 11 Jul 2022, 23:27
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The peaks of a mountain range, acting like rocks in a streambed, produce ripples in the air flowing over them; the resulting flow pattern, with crests and troughs that remain stationary although the air that forms them is moving rapidly, are known as "standing waves."

Elimination Sequence: D,E then A,B

'the resulting flow pattern' is an appositive phrase (noun modifying noun) which need a noun and needs it quick! (noun modifiers must be close). All options have a noun to be modified right after ',' but option C and D use the subordinating conjunction 'although' to connect the fragment 'stationary crests and troughs'. Subordinating conjunctions can connect an independent clause with a dependent clause(which must have a subject and a verb). Ditch D,E

(A) crests and troughs that remain stationary although the air that forms them is moving rapidly, are - the flow pattern (singular) needs is (singular) Out!

(B) crests and troughs that remain stationary although they are formed by rapidly moving air, are - the flow pattern (singular) needs is (singular). Nope, Out!

(C) crests and troughs that remain stationary although the air that forms them is moving rapidly, is - the flow pattern (singular) needs is (singular), Good.

(D) stationary crests and troughs although the air that forms them is moving rapidly, are

(E) stationary crests and troughs although they are formed by rapidly moving air, is
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The peaks of a mountain range, acting like rocks in a streambed, produ 31 Aug 2022, 16:13
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rikinmathur
The ”air is moving” in C threw me off in this question and thus, I ignored the parallelism error in E which I now understand. But can someone explain why “air is moving rapidly” is correct? To me it should be moves and is moving should be wrong since it is not a thing happening currently in the continuous tense.

GMATNinja any ideas on this?
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There's nothing inherently wrong with saying that one thing happens while another thing is happening. Here, have an example:

    "Tim smiles even though his children are smearing spaghetti sauce all over the walls."

The sentence is perfectly clear and reasonable, right? It would be fine to use the same tense for both actions, but it's also OK to have two slightly different tenses here -- the sentence still makes sense, and the use of two different tenses certainly isn't a definite error.

In choice (C), perhaps the author wants to differentiate between the relatively fixed and constant nature of the first action (the "crests and troughs that remain stationary") and the flux and movement of the second action (the air that "is moving rapidly")?

More importantly, the "rules" governing the use of simple present and present continuous are awfully subjective, so we just don't have a solid reason to eliminate (C) based solely on the tenses here. Your best bet is to be conservative and look for other, better decision points.

For more on GMAT verb tenses, check out this video or this one.

I hope that helps a bit!
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The peaks of a mountain range, acting like rocks in a streambed, produ 27 Sep 2022, 09:19
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anshunadir
I will try to break the tie between C and E.

Although rule : The pronoun after although does not refers to the nearest noun, but to the first noun in the sentence.

The sentence with option E is:
the resulting flow pattern, with stationary crests and troughs although they are formed by rapidly moving air, is known as “standing waves.”

According to the above rule, they refers to resulting flow pattern and not to stationary crests and troughs.

Hence, C wins.
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Is there any rule around "Although" in general.
GMATNinja Could you please clarify if any.
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The peaks of a mountain range, acting like rocks in a streambed, produ 30 Sep 2022, 05:13
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TeenaChoudhary
anshunadir
I will try to break the tie between C and E.

Although rule : The pronoun after although does not refers to the nearest noun, but to the first noun in the sentence.

The sentence with option E is:
the resulting flow pattern, with stationary crests and troughs although they are formed by rapidly moving air, is known as “standing waves.”

According to the above rule, they refers to resulting flow pattern and not to stationary crests and troughs.

Hence, C wins.


Is there any rule around "Although" in general.
GMATNinja Could you please clarify if any.
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Hello TeenaChoudhary,

We hope this finds you well.

To answer your query, there is really no such rule related to "Although" and pronouns; pronouns used within or alongside an "Although" phrase act more or less the same as they do in the context of other modifying phrases.

We hope this helps.
All the best!
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The peaks of a mountain range, acting like rocks in a streambed, produ 01 Oct 2022, 03:02
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(C) crests and troughs that remain stationary although the air that forms them is moving rapidly, is


Can someone please explain why it shouldn't be remains instead of remain?
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The peaks of a mountain range, acting like rocks in a streambed, produ 27 Oct 2022, 07:22
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(C) crests and troughs that remain stationary although the air that forms them is moving rapidly, is


Can someone please explain why it shouldn't be remains instead of remain?
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What is it that remain(s) stationary? The crests AND troughs. Note that "crests and troughs" is plural -= you'd say, "The crests and troughs ARE large," not "The crests and troughs IS large."

So the "that" in choice (C) refers to "crests AND troughs," and since crests and troughs is plural, we need a plural form of the verb ("remain").

I hope that helps!
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The peaks of a mountain range, acting like rocks in a streambed, produ 02 Sep 2023, 01:40
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Quote:
The peaks of a mountain range, acting like rocks in a streambed, produce ripples in the air flowing over them; the resulting flow pattern, with crests and troughs that remain stationary although the air that forms them is moving rapidly, are known as "standing waves."


(A) crests and troughs that remain stationary although the air that forms them is moving rapidly, are

(B) crests and troughs that remain stationary although they are formed by rapidly moving air, are

(C) crests and troughs that remain stationary although the air that forms them is moving rapidly, is

(D) stationary crests and troughs although the air that forms them is moving rapidly, are

(E) stationary crests and troughs although they are formed by rapidly moving air, is
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Hi AjiteshArun ,

Thank you for your free SC videos . They are really helpful.

Coming to my question,

In Option E , I read a reply which said " When we have "although" in front of a clause, we need to contrast with another clause, either preceding or following. So if I say "although they are formed by rapidly moving air," I need to contrast with another clause, such as "they remain stationary." We can't say with noun, although clause, unless I am contrasting with some earlier action, such as "I argued with my brothers, although I knew they were right."

Can I consider this as LEVEL 1 error ? Do we need a clause before or after although for comparison purpose ? Or is this a LEVEL 3 error ?

Also, I found Option E grammatically correct. Even though this is a 650-700 level question , I found it 700+.
I could not decide between C and E.
What is the other way to reject Choice E if one is not aware of the Although rule ?

In-addition ,
Most of the replies say Option C is right because the noteworthy thing that the crests and troughs are stationary even though they are formed by rapidly moving air is captured by Option C.

But I could not understand that the AUTHOR wanted to convey this ( the above) meaning .

How do I understand what the author wants to convey ? ( I know this is a very broad question , but it becomes difficult for me to understand the intended meaning that the author wants to convey )

Regards
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The peaks of a mountain range, acting like rocks in a streambed, produ 02 Sep 2023, 23:17
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Iwillget770
Hi AjiteshArun ,

Thank you for your free SC videos . They are really helpful.

Coming to my question,

In Option E , I read a reply which said " When we have "although" in front of a clause, we need to contrast with another clause, either preceding or following. So if I say "although they are formed by rapidly moving air," I need to contrast with another clause, such as "they remain stationary." We can't say with noun, although clause, unless I am contrasting with some earlier action, such as "I argued with my brothers, although I knew they were right."

Can I consider this as LEVEL 1 error ? Do we need a clause before or after although for comparison purpose ? Or is this a LEVEL 3 error ?

Also, I found Option E grammatically correct. Even though this is a 650-700 level question , I found it 700+.
I could not decide between C and E.
What is the other way to reject Choice E if one is not aware of the Although rule ?

In-addition ,
Most of the replies say Option C is right because the noteworthy thing that the crests and troughs are stationary even though they are formed by rapidly moving air is captured by Option C.

But I could not understand that the AUTHOR wanted to convey this ( the above) meaning .

How do I understand what the author wants to convey ? ( I know this is a very broad question , but it becomes difficult for me to understand the intended meaning that the author wants to convey )

Regards
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Hi Iwillget770,

I'm glad you found the video lessons helpful. :)

You're right. If we see something like {noun + although...}, we need a verb for that initial noun.

1. The report, although incomplete, is quite useful.

2. The report, although it is incomplete.

If an option doesn't give us a subject-verb pair around an although, we should take it out. This kind of error is quite easy to spot in a simple sentence, but could be harder to spot when the although is embedded in another dependent clause. You don't, however, have to remember this as a rule if you don't want to, because you may be able to see that the structure is incomplete. Have a look at option E:

tejal777
(E) stationary crests and troughs although they are formed by rapidly moving air, is
Show more
When you read this, do you get the feeling that the idea introduced by stationary crests and troughs isn't complete? That's a really good reason to remove E (level 1 :)).

We could also take E out on the basis of a meaning call. Option E drops the verb remain. As a result, the contrast is no longer as good, because what we want to say is:

a. The air that forms the C&T is moving rapidly.
b. Because of this rapid movement, we would normally not expect the C&T to stay stationary.
c. But the C&T do stay stationary even though the air that forms them is moving rapidly.

Option E uses only stationary before crests and troughs. It doesn't use the word remain, and therefore doesn't do as good a job of communicating that the crests and troughs stay stationary.

Finally, option E uses the passive are formed, but this is a level 3 call, and we should try to prioritise either the structure call or the meaning call.
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