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555-605 Level|   Parallelism|                  
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AryamaDuttaSaikia
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Recently implemented "shift-work equations" based on studies of the hu 25 Sep 2015, 21:32
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The comma before "And" does not necessarily suggest that the last item in the parrallel list be "Independent clause"

AND - is used to join entities

X, & Y - If X is IC then Y needs to be IC to maintain parallelism.

In this case, X,Y, Z, & A - The last element is not parallel with the remaining 3 elements. The last element is out of sync. So, it needs to be removed.

The correct option (C) - does the same. X - Have reduced sickness , Y - Have reduced sleeping, Z - Have reduced fatigue,
A - contrast (represented by While) - Raising production efficiency.
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Recently implemented "shift-work equations" based on studies of the hu 31 Mar 2016, 03:36
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AryamaDuttaSaikia
The comma before "And" does not necessarily suggest that the last item in the parrallel list be "Independent clause"

AND - is used to join entities

X, & Y - If X is IC then Y needs to be IC to maintain parallelism.

In this case, X,Y, Z, & A - The last element is not parallel with the remaining 3 elements. The last element is out of sync. So, it needs to be removed.

The correct option (C) - does the same. X - Have reduced sickness , Y - Have reduced sleeping, Z - Have reduced fatigue,
A - contrast (represented by While) - Raising production efficiency.
Show more

But why not D? I thought D put the sentence in parallel construction.
Thank you in advance!
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Recently implemented "shift-work equations" based on studies of the hu 03 Apr 2016, 08:10
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AryamaDuttaSaikia
The comma before "And" does not necessarily suggest that the last item in the parrallel list be "Independent clause"

AND - is used to join entities

X, & Y - If X is IC then Y needs to be IC to maintain parallelism.

In this case, X,Y, Z, & A - The last element is not parallel with the remaining 3 elements. The last element is out of sync. So, it needs to be removed.

The correct option (C) - does the same. X - Have reduced sickness , Y - Have reduced sleeping, Z - Have reduced fatigue,
A - contrast (represented by While) - Raising production efficiency.

But why not D? I thought D put the sentence in parallel construction.
Thank you in advance!
Show more

As per option D, the "equations" have done 3 things (depicted by 3 verbs):
1. reduced 2 things (sickness and sleeping on job).
2. lowered fatigue.
3. raised production.

In such construction, please note that the 1st part should be ......reduced sickness AND sleeping on the job. The conjunction "and" is missing between sickness and sleeping in option D. Therefore option D is wrong.

Now for the correct option C:
Shift-work equations have reduced 3 things: 1. sickness, 2.sleeping on job, and 3. fatigue.
However, the equations have increased 1 thing: production
The contrast between increase and decrease is better depicted by the contrast marker "while" rather than "and".

Nonetheless, using "and" could be grammatically correct, if that constructional error mentioned above were not there in option D.
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Recently implemented "shift-work equations" based on studies of the hu 05 Apr 2016, 22:26
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Dear R26, I guess you mean the comma after the word “job”. When I look at the sentence, it seems not to be underlined. However, I don’t think you need to worry about this comma. The equations have reduced three things. The second and third thing must be separated by “and”. Whether there is a comma there or not doesn’t matter. Eliminate A, B and D. As mentioned, “was lowered” in E is redundant. Choose C. Fortunately, the GMAT is not a test of punctuation!
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Recently implemented "shift-work equations" based on studies of the hu 14 Apr 2016, 22:44
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The sentence is in two parallel parts. The first part says "shift-work equations" has 1."reduced sickness", 2. "sleeping on the job",and 3."fatigue.". The second part of the sentence is the result of 1,2, and 3 which is raising production efficiency. Hence raising is the result of these three actions. Hence it should be in " ing " form. The answer therefore cannot be "B" and is "C."
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Recently implemented "shift-work equations" based on studies of the hu 09 May 2016, 04:16
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I know it changes the meaning, but would a sentence like this be correct?

Recently implemented "shift-work equations" based on studies of the human sleep cycle have reduced sickness, sleeping on the job, fatigue among shift workers, and production efficiency in various industries.

Honestly I can't understand the rule used to arrive to choice C... There seem to be 10 different opinions and I couldn't see a solid rule that could be applied in all cases (99% of cases)

Can we have a list with, say 10 elements? "I like 1,2,3,4,5,6,7,8,9, and 10" ? There is no limit to the number of elements in a list, since they are all parallel, right?

Another one, somebody used this way to see it and this one does make sense to be a solid rule:

Recently implemented "shift-work equations" based on studies of the human sleep cycle have reduced sickness, have reduced sleeping on the job, have reduced fatigue among shift workers, and have reduced have raised production efficiency in various industries. -> Wrong, doesn't make sense, need to change.

Is this way to analyse it correct?

Thank you!
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Recently implemented "shift-work equations" based on studies of the hu 09 May 2016, 06:45
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iliavko
I know it changes the meaning, but would a sentence like this be correct?

Recently implemented "shift-work equations" based on studies of the human sleep cycle have reduced sickness, sleeping on the job, fatigue among shift workers, and production efficiency in various industries.
Show more
To say that this sentence changes the meaning, would be too mild. This sentence is actually not making any sense. This is suggesting that recently implemented "shift-work equations" have reduced four things:

i) sickness
ii) sleeping on the job,
iii) fatigue among shift workers and
iv) production efficiency

The reason this does not make sense, is because if sickness, sleeping, and fatigue are reduced, there is no reason why production efficiency should also reduce.

Quote:
Another one, somebody used this way to see it and this one does make sense to be a solid rule:

Recently implemented "shift-work equations" based on studies of the human sleep cycle have reduced sickness, have reduced sleeping on the job, have reduced fatigue among shift workers, and have reduced have raised production efficiency in various industries. -> Wrong, doesn't make sense, need to change.

Is this way to analyse it correct?
Show more
Absolutely. In fact, our book EducationAisle Sentence Correction Nirvana discusses the parallelism philosophy through a simplified XYZ deconstruct, its application and examples in significant detail. If someone is interested, PM me your email-id, I can mail the corresponding section.
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Recently implemented "shift-work equations" based on studies of the hu 09 May 2016, 07:23
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yes, yes I understand it makes no sense, but for example purposes, imagine that it does make sense for some reason, then the list would be correct? Is there a limit to the number of elements you can list? No, right?..
But it seems that on Gmat they like to use "1,2 and 3"-lists, so 3elements in parallel and then something else happens.

Let's make the example sentence more logical:

Recently implemented "shift-work equations" based on studies of the human sleep cycle have reduced sickness, sleeping on the job, fatigue among shift workers, and labor accidents in various industries. -> would this be correct? Here I don't like the (comma)-And formation, wouldn't it require an Independent clause? I'm a bit confused with this...

And good to know that the XYZ analysis works. Its good to have a checker-rule!

Thank you.
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Recently implemented "shift-work equations" based on studies of the hu 09 May 2016, 09:42
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yes, yes I understand it makes no sense, but for example purposes, imagine that it does make sense for some reason, then the list would be correct? Is there a limit to the number of elements you can list? No, right?..
Show more
Correct.

Quote:
Let's make the example sentence more logical:

Recently implemented "shift-work equations" based on studies of the human sleep cycle have reduced sickness, sleeping on the job, fatigue among shift workers, and labor accidents in various industries. -> would this be correct?
Show more
Yes.

Quote:
Here I don't like the (comma)-And formation, wouldn't it require an Independent clause? I'm a bit confused with this...
Show more
It's just a list (more than 2 elements), and hence, there is a comma. Another officially correct sentence:

Twenty-two feet long and 10 feet in diameter, the AM-1 is one of the many new satellites that are part of a 15-year effort to subject the interactions of Earth's atmosphere, ocean, and land surfaces to detailed scrutiny from space.

Notice the comma before and land surfaces.

Having said that, the presence or absence of comma before and should not be a reason for you to select/ignore an option.
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Recently implemented "shift-work equations" based on studies of the hu 29 Aug 2016, 08:57
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One question. Raising is not parallel with have reduced. I think the correct answer would have been: and fatigue among shift workers while they have raised...

Am I right???
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Recently implemented "shift-work equations" based on studies of the hu 31 Aug 2016, 07:26
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Mariwa
One question. Raising is not parallel with have reduced. I think the correct answer would have been: and fatigue among shift workers while they have raised...

Am I right???
Show more

Consider "while" not as a parallelism marker, but as a contrast marker.

Consider the sentence this way:

Independent clause, present participle modifier (modifying the entire clause preceding it):
Equations have reduced fatigue, (while) raising the efficiency.

Since the modification is to show a contrast, "while" is added before the present participle.

Since this is an official question, it can be inferred that GMAC accepts such use of "while", though I do agree that the sentence you have mentioned is better.
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Recently implemented "shift-work equations" based on studies of the hu 09 Sep 2018, 01:27
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skim
The Official Guide for GMAT Review, 10th Edition, 2003

Practice Question
Question No.: SC 233
Page: 690
Recently implemented "shift-work equations" based on studies of the human sleep cycle have reduced sickness, sleeping on the job, fatigue among shift workers, and have raised production efficiency in various industries.

(A) fatigue among shift workers, and have raised

(B) fatigue among shift workers, and raised

(C) and fatigue among shift workers while raising

(D) lowered fatigue among shift workers, and raised

(E) and fatigue among shift workers was lowered while raising


Show SpoilerOE
The best answer, C, grammatically states that the equations... have reduced x, y, and i. and have raised efficiency. Choices A and B fail to use and to signal that fatigue among shift workers completes the series begun by have reduced, and so produce awkward and unclear sentences. Both D and E fail to use and to introduce the last item in the list, which is sleeping in these constructions. In E, while raising has no logical referent, producing only the absurd statement that fatigue has raised efficiency.


Show Spoiler
This is question #134 of the 12th ed OG. I don't understand why in option (D), the OE states: "lowered before fatigue illogically suggests that fatigue actually increased"

On a separate note, what is the difference between "among" and "amongst" in GMAT context? Is there any particular rule pertaining to these two words?
Show more

GMATNinja , egmat , VeritasKarishma , MartyMurray

I am finding it difficult to accept C as the answer choice. As per my understanding, "while" is a subordinator and required a bonafide verb which is clearly missing here in option C. Can anybody please help me understand?
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Recently implemented "shift-work equations" based on studies of the hu 09 Sep 2018, 13:29
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Recently implemented "shift-work equations" based on studies of the human sleep cycle have reduced sickness, sleeping on the job, fatigue among shift workers, and have raised production efficiency in various industries.

(C) and fatigue among shift workers while raising

I am finding it difficult to accept C as the answer choice. As per my understanding, "while" is a subordinator and required a bonafide verb which is clearly missing here in option C. Can anybody please help me understand?
Show more

"While" can be used in two ways.

It can be used to start a clause. In such cases "while" is similar to "whereas," and the clause so begun is a subordinate clause.

"While" can also be used to convey, simply, "at the same time", without the connotations of the word "whereas." When used in this way, "while" can be used to begin a clause, but what follows "while" that means "at the same time" does not have to be a clause.

Consider the following examples:

"While" Begins Clause: While the guests were enjoying the sunset, the band set up.

The above sentence conveys that the band set up as the guests were enjoying the sunset.

"While" Without Clause: While setting up, the band members discussed the song list.

This above sentence conveys that, as they were setting up, the band members discussed the song list.

"While Without Clause: My uncle Harry would sing opera while skiing in the Alps.

Notice, in this last sentence, there is no comma before "while". When "while" means "when", you don't need a comma before it. When "while" means "whereas" and begins a clause, the clause has to be separated from the rest of the sentence by a comma.

Here's another example without a comma:

We ran around town while our parents were shopping for bicycles.

The fact that "while" is not preceded by a comma confirms that, in this case, it does not mean "whereas".
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Recently implemented "shift-work equations" based on studies of the hu 10 Sep 2018, 23:47
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skim
The Official Guide for GMAT Review, 10th Edition, 2003

Practice Question
Question No.: SC 233
Page: 690
Recently implemented "shift-work equations" based on studies of the human sleep cycle have reduced sickness, sleeping on the job, fatigue among shift workers, and have raised production efficiency in various industries.

(A) fatigue among shift workers, and have raised

(B) fatigue among shift workers, and raised

(C) and fatigue among shift workers while raising

(D) lowered fatigue among shift workers, and raised

(E) and fatigue among shift workers was lowered while raising


Show SpoilerOE
The best answer, C, grammatically states that the equations... have reduced x, y, and i. and have raised efficiency. Choices A and B fail to use and to signal that fatigue among shift workers completes the series begun by have reduced, and so produce awkward and unclear sentences. Both D and E fail to use and to introduce the last item in the list, which is sleeping in these constructions. In E, while raising has no logical referent, producing only the absurd statement that fatigue has raised efficiency.


Show Spoiler
This is question #134 of the 12th ed OG. I don't understand why in option (D), the OE states: "lowered before fatigue illogically suggests that fatigue actually increased"

On a separate note, what is the difference between "among" and "amongst" in GMAT context? Is there any particular rule pertaining to these two words?

GMATNinja , egmat , VeritasKarishma , MartyMurray

I am finding it difficult to accept C as the answer choice. As per my understanding, "while" is a subordinator and required a bonafide verb which is clearly missing here in option C. Can anybody please help me understand?
Show more

An adverb clause can be reduced to an adverbial phrase if it has the same subject as the main clause.

While I was skiing, I saw ...
is same as
While skiing, I saw ...

It reflects that the two happened "at the same time".


Recently implemented "shift-work equations" ... have reduced A, B, and C while raising production efficiency ...

is same as

Recently implemented "shift-work equations" ... have reduced A, B, and C while they are raising production efficiency ...
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Quote:
skim
Recently implemented "shift-work equations" based on studies of the human sleep cycle have reduced sickness, sleeping on the job, fatigue among shift workers, and have raised production efficiency in various industries.

(A) fatigue among shift workers, and have raised

(B) fatigue among shift workers, and raised

(C) and fatigue among shift workers while raising

(D) lowered fatigue among shift workers, and raised

(E) and fatigue among shift workers was lowered while raising
Show more

AjiteshArun GMATNinja,

I have a questions here.
Need support to eliminate option A. I am not satisfied with mentioned answers.
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Harsh2111s
AjiteshArun GMATNinja,

I have a questions here.
Need support to eliminate option A. I am not satisfied with mentioned answers.
Show more
Hi Harsh2111s,

Let's take a look at the list:

Recently implemented "shift-work equations" based on studies of the human sleep cycle have reduced
(a) sickness,
(b) sleeping on the job,
(c) fatigue among shift workers,
and
(d) have raised production efficiency

The first three are nouns, and make sense with have reduced (have reduced sickness, have reduced sleeping, have reduced fatigue), but after that, we run into a verb phrase (have raised...) instead of a noun, and we end up with have reduced have raised production efficiency as the final element in the list.
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Recently implemented "shift-work equations" based on studies of the hu 06 May 2020, 07:12
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Quote:
Let's take a look at the list:

Recently implemented "shift-work equations" based on studies of the human sleep cycle have reduced
(a) sickness,
(b) sleeping on the job,
(c) fatigue among shift workers,
and
(d) have raised production efficiency

The first three are nouns, and make sense with have reduced (have reduced sickness, have reduced sleeping, have reduced fatigue), but after that, we run into a verb phrase (have raised...) instead of a noun, and we end up with have reduced have raised production efficiency as the final element in the list.
Show more
[/quote]

But I think have is used to make things parallel.
Recently implemented "shift-work equations" based on studies of the human sleep cycle have reduced sickness, sleeping......,fatigue.....(have reduced sickness, have reduced sleeping, have reduced fatigue))and

Recently implemented "shift-work equations" based on studies of the human sleep cycle have raised production efficiency.

Need some more input.
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Harsh2111s
But I think have is used to make things parallel.
Recently implemented "shift-work equations" based on studies of the human sleep cycle have reduced sickness, sleeping......,fatigue.....(have reduced sickness, have reduced sleeping, have reduced fatigue))and

Recently implemented "shift-work equations" based on studies of the human sleep cycle have raised production efficiency.

Need some more input.
Show more
Hi Harsh2111s,

That's one way of looking at it, but then we'd really need two lists, which would in turn mean that we'd expect to see two conjunctions in the sentence.

Equations have reduced (X, Y, and Z), and have raised (B).

To see why it'd be much better to include the second conjunction, check if you'd be comfortable with the following sentence:

Equations have reduced X, Y, and have raised B.
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Will it be correct if the sentence structure in A is as below

'have reduced X,Y and Z and have raised'

Can someone please clarify?
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GMAT Focus 1: 715 Q83 V90 DI83
GMAT 1: 780 Q50 V51
GRE 1: Q170 V169
Posts: 5,949
Kudos: 5,080
Recently implemented "shift-work equations" based on studies of the hu 06 May 2020, 10:18
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NimishaKrishna
Will it be correct if the sentence structure in A is as below

'have reduced X,Y and Z and have raised'

Can someone please clarify?
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Hi NimishaKrishna,

Doing that would certainly remove that particular error, but it is hard to say whether option A would then be "correct". Generally, we should avoid evaluating altered options, because we'd then be going by our own opinions, instead of those of the GMAT.
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