Sentence Correction

Can someone comment on the grammar structure of 1 through 3? Which one is correct / incorrect? And what is the implied meaning of each. Thanks.

1) Nuclear fusion is the force that powers the Sun, the stars, and hydrogen bombs, merging the nuclei of atoms and .....
(merging here expands on the idea of what NF does)

2) Nuclear fusion is the force that powers the Sun, the stars, and hydrogen bombs, and merges the nuclei of atoms and .....
(Seems to imply NF does two separate things: 1) powers and 2) merges)

3) Nuclear fusion is the force that powers the Sun, the stars, and hydrogen bombs, and that merges the nuclei of atoms and .....
(Do you need "that" here? I've seen this structure a lot and it is correct: X is the thing that does Y, modifier, and that does Z. Does it apply here? [Not that " the stars, and HB" is the modifier of the Sun])? Difference between 2 and 3?

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Original Problem:

Nuclear fusion is the force that powers the Sun, the stars, and hydrogen bombs, merging the nuclei of atoms and not splitting them apart, as in nuclear reactors.

(A) merging the nuclei of atoms and not splitting them apart, as in nuclear reactors
(B) merging the nuclei of atoms instead of splitting them apart, like nuclear reactors
(C) merging the nuclei of atoms rather than splitting them apart, as nuclear reactors do
(D) and merges the nuclei of atoms but does not split them apart, as is done in nclear reactors
(E) and merges the nuclei of atoms, unlike atomic reactors that split them apart

Hi gmatusa2010,

You ask an excellent question about a grammatical structure that confuses many test-takers. Your comments on the three examples seem to indicate that you actually understand the structure quite well. In the sentence "Nuclear fusion is the force that powers the Sun, the stars, and hydrogen bombs, merging the nuclei of atoms and...." the structure "merging the nuclei of atoms and..." is a participial modifying phrase that is tacked on to the end of the sentence with a comma (fortunately, you do not have to understand difficult grammar terminology for the GMAT!...just make sure you learn to recognize commonly used structures such as this). As you stated, it is indeed giving the reader more information about nuclear fusion and how it powers the Sun, the stars, and hydrogen bombs. This example is correct. When participial phrases are tacked on to the end of a sentence or a clause with a comma, they are used to modify the subject of the sentence/clause after some action is given first. Consider this sentence that I use in my classes to better clarify this structure: "Nadal beat Federer in 5 sets, shocking the tennis world." What role is "shocking the tennis world" playing in that sentence? It is modifying the subject of the sentence (in this case Nadal) and what Nadal did by beating Federer in 5 sets. While participial phrases must always have a noun to modify in a sentence, a good way to think about these phrases when they are used this way is that they are modifying the subject and giving some consequence or result of the subject's action. The trick here (and why these structures are used so much by official test makers) is that many test takers think that the sentence in your first example is not parallel and that "merging" needs to be "and merges". Remember that in this example "merging" is not a verb but a modifier, and the meaning would be incorrect if it said "and merges" (as you point out in your comment). Nuclear fusion is not powering the sun, the stars, and hydrogen bombs and then separately merging the nuclei of atoms. Additionally, the "and merges" could not follow a comma as that would be a comma splice. For your third example, the additional that is unnecessary and maintains the same problem that exists in the second example. They are not separate things and the participial structure is the perfect way to show that. OG 12th Edition SC numbers 30 and 47 are two additional examples if you would like to see more of this structure in action. Hope this helps!

chris@veritasprep wrote:Hi gmatusa2010,

Nuclear fusion is not powering the sun, the stars, and hydrogen bombs and then separately merging the nuclei of atoms. Additionally, the "and merges" could not follow a comma as that would be a comma splice.

Hi chris can you explain whats a comma splice.Does it make the sentence incorrect?

I think B is correct.HEre the sentence after merging is modifying the subject as rightly pointed out by chris !

"Nuclear fusion is the force that powers the Sun, the stars, and hydrogen bombs ..."

Why isn't it '...the hydrogen bombs' to maintain the parallelism? Pleases could anyone answer this.

clammiestqasar,

Strictly speaking, comma splices exist when two independent clauses are improperly linked with a comma without a coordinating conjunction.

An example of a comma splice would be the following: Bill lives in New York, John lives in San Francisco. Clearly this would require some type of conjunction to make the sentence correct.

Corrected example: Bill lives in New York, and John lives in San Francisco.

In my reference on the preceding post, I am using the term comma splice liberally as it a distinct comma error but not the exact definition of a "comma splice". Any time a comma is improperly separating two clauses I tend to refer to it as a "comma splice" as it is an accurate description of the problem

In the SC problem discussed in this post answer choices D and E can be eliminated immediately because of a comma problem. When a subject commands two different verbs it is improper to insert a comma between them. Here would be a simple example of the comma error (improperly inserted comma) that I am referring to:

John lives in New York, and works in New Jersey.

The two verbs - lives and works - are commanded by the same subject John and the two clauses are not independent. Clearly there can be no comma there and the corrected sentence must be: John lives in New York and works in New Jersey.

When connecting clauses, you should only use a comma with a conjunction when the clauses are independent (stand alone sentences). Consider the following example where the comma is required: John lives in New York, but his wife lives in California. In this example, you must have a comma as there are two separate subjects with verbs forming independent clauses.

To put this understanding to work with the example in this post, you can see that answer choices D and E are flawed. After getting rid of the garbage in the sentence (eliminating everything but the key structures in the sentence - one of the key strategies in GMAT SC!) the sentences in D and E read like this: Nuclear fusion is the force that powers......, and merges. To eliminate the comma error the sentence would have to read: Nuclear fusion is the force that powers.....and merges. However, as discussed in the post already, this would still be incorrect because of the meaning problems discussed in my previous reply. Hope this helps your understanding of proper comma usage!

Correction: that last post was directed to mundasingh123 not clammiestqasar. Apologies!

Hey Chris,

Great explanation. I am getting VERBing as a consequence questions mostly right. One question that stumped me is Q26 in OG12, I'll just right the option that's confusing me and is relevant to this topic:

Emily Dickinson's letters to Susan Huntington Dickinson were written over a period beginning a few years before Susan's marriage to Emily's brother and ending shortly before Emily's death in 1886, outnumbering her letters to anyone else

This looks good construction to me. Emily Dickinson's letters is the subject and consequence to "were written" is outnumbering. Can yu please explain why this is wrong?

Also, would this be correct usage:
Emily Dickinson wrote letters to Susan Huntington Dickinson over a period beginning a few years before Susan's marriage to Emily's brother and ending shortly before Emily's death in 1886, outnumbering her letters to anyone else.

Thanks.

Hi akg123,

You bring up an excellent question from the O.G. that I often use with students to discuss these issues.

It would seem that your example is correct much in the same way that "Nadal beat Federer in 5 sets, shocking the tennis world." is correct. A closer look, though, shows that the passive voice cannot be used in combination with this structure.

On the GMAT, the passive voice is not strictly incorrect unless it causes a meaning problem or an error of parellism/structure. For instance there is nothing incorrect with the sentence: "A mistake was made." However, this passive structure can cause problems in more complicated sentences.

Consider this example: A mistake was made by John on one of the crucial questions, lowering his overall score.

If you are going to use this type of participial modifier at the end of a sentence/clause, it needs to logically modify the subject and the subject should be the perpetrator of the action (active voice not passive voice). Clearly, as in your example, the noun "mistake" can be logically modified by "lowering his overall score" but is not the active subject so this is problematic.

In your example there is the same problem: Letters were written over a time period, outnumbering her letters to anyone else. The passive structure is the problem and that is why the official explanation states that it is unclear what outnumbering is referring to.

Take another correct example from an official guide question using this participial structure:

Five fledgling sea eagles left their nests in western Scotland this summer, bringing to 34 the number of wild birds successfully raised since transplants from Norway began in 1975.

If this was written: "Nests were left by five fledging sea eagles in western Scotland this summer, bringing to 34 the number of wild birds successfully raised since transplants from Norway began in 1975." it would be incorrect in the same way your example is. Hope this helps!

chris@veritasprep : a BIG thanks really for the post just above. How ing modifier is different for active and passive voice . It made my day . In many problems, I accepted ,though, I was left not fully convinced why rather 'how' sometimes ing modifier was ok in modifying subject and some other times not ok. Excellent !

Question: Do you have example of any other OG problem or GMATPrep in which the construction is voilated in the same way ? I am trying to search as well some GMATPrep questions to reinforce the learning.

One GMAT Prep question not with passive construction but ,definitely , will add value to ongoing discussion .

Industrialization and modern methods of insect control have improved the standard of living around the globe while at the same time they have introduced some 100,000 dangerous chemical pollutants, having gone virtually unregulated since they were developed more than 50 years ago.

(A) while at the same time they have introduced some 100,000 dangerous chemical pollutants, having
(B) while at the same time introducing some 100,000 dangerous chemical pollutants that have
(C) while they have introduced some 100,000 dangerous chemical pollutants at the same time, which have
(D) but introducing some 100,000 dangerous chemical pollutants at the same time that have
(E) but at the same time introducing some 100,000 dangerous chemical pollutants, having

Could you discuss the options A and E in context of the discusssion above .
OA is B

An another challenging one :

A study of food resources in the North Pacific between 1989 and 1996 revealed that creatures of the seabed were suffering from dwindling food supplies, possibly resulting from increasing sea surface temperatures during the same period.

(A) that creatures of the seabed were suffering from dwindling food supplies, possibly resulting from increasing
(B) that creatures of the seabed were suffering because food supplies were dwindling, possibly as a result of an increase in
(C) that creatures of the seabed were suffering because of food supplies, which were dwindling possibly as a result of increasing
(D) creatures of the seabed that were suffering from food supplies that were dwindling, possibly resulting from an increase in
(E) creatures of the seabed that were suffering because food supplies were dwindling, which possibly resulted from increasing
OA is B
- Should resulting be treated differant from other ing modifiers ?

Chris, You are just great! Thanks.

OA please

OA - E (for the fusion qstn)