GMAT Sentence Correction: How to Find the Core Sentence (Part 7)

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Manhattan Prep GMAT Blog - GMAT Sentence Correction: How to Find the Core Sentence (Part 7) by Stacey Koprince

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Welcome to the latest installment of our Core Sentence series on GMAT Sentence Correction problems! If you haven’t seen this series before, start here.

Last time, we talked about how the test-writers will sometimes use a full-sentence underline to distract you with a lot of different changes—when there’s one “big” change sitting right in front of you that you can use to eliminate all or most of the 4 wrong answers.

I’ve got another full-underline SC for you, also from the GMATPrep® free exams, but maybe with some different angles this time… Go for it!

* “There are no legal limits, as there are for cod and haddock, on the size of monkfish that can be caught, a circumstance that contributes to their depletion through overfishing.

“(A) There are no legal limits, as there are for cod and haddock, on the size of monkfish that can be caught, a circumstance that contributes to their depletion through overfishing.

“(B) There are no legal limits on the size of monkfish that can be caught, unlike cod or haddock, a circumstance that contributes to depleting them because they are being overfished.

“(C) There are legal limits on the size of cod and haddock that can be caught, but not for monkfish, which contributes to its depletion through overfishing.

“(D) Unlike cod and haddock, there are no legal size limits on catching monkfish, which contributes to its depletion by being overfished.

“(E) Unlike catching cod and haddock, there are no legal size limits on catching monkfish, contributing to their depletion because they are overfished.”

Ready? Let’s do this!

Our standard GMAT Sentence Correction Process has us start with a First Glance—a look at the beginning of the underline and how that changes in each of the five answers. My first thought? The word There is useless.

But! I did notice something as I scanned down those answers. Choices (D) and (E) both start with the word Unlike! Boom: I know there’s a comparison (or a contrast, actually) going on. Given that the opener of the original sentence told me nothing, this is really useful to know.

Okay, let’s read the sentence and see what it means:

“There are no legal limits, as there are for cod and haddock, on the size of monkfish that can be caught, a circumstance that contributes to their depletion through overfishing.”

Even though there’s no obvious contrast marker (like unlike), I know to look for a contrast and I’ve spotted it: Monkfish don’t have legal limits on size, but cod and haddock do. That complete thought takes me through this much of the sentence:

“There are no legal limits, as there are for cod and haddock, on the size of monkfish that can be caught, …”

That is a complete sentence. Is the whole thing the core sentence? Or can I strip any part of it out as “extra?”

“There are no legal limits, as there are for cod and haddock, on the size of monkfish that can be caught, …”

I can ignore the comparison part, actually—the stuff between the commas. Let your eyes sort of skip over it and concentrate just on the main information. The core sentence is really just this info about the monkfish.

Now, what comes after that last comma?

“… a circumstance that contributes to their depletion through overfishing.”

That’s not a complete sentence. If this part is correct, then, these words must be acting as a modifier. Let’s see…

“There are no legal limits, as there are for cod and haddock, on the size of monkfish that can be caught, a circumstance that contributes to their depletion through overfishing.”

The words a circumstance refer back to the situation described in the core. This is the circumstance: There are no legal limits on the size of monkfish that we’re allowed to catch.

If that’s true, does it make sense that this could lead to their depletion? Yes, definitely. Okay, so this modifier makes sense.

Now you have a choice, since the whole sentence is underlined. Do you want to look at the other modifier portions in the other choices to see what else you can eliminate on that potential issue? Or would you rather loop back around to the comparison and deal with that?

I personally find comparisons easier, so I’m going to start there. (But I’ll show you the modifier part later, too.)

Okay, what about that comparison? Is it properly made in the original sentence?

“There are no legal limits, as there are for cod and haddock, on the size of monkfish that can be caught, …”

I’m not 100% sure, actually. This does sound a little funny—they’re mentioning the cod and haddock before even saying monkfish. Maybe the Unlike setup I spotted in the later answers will be better?

Time to compare the answers—efficiently. Which parts do I need to look at? Since I just want to look at the comparison issue, I can ignore the ending modifier stuff for now.

Also, note that the first three sentences have a different structure than the final two—so deal with each in a group.

“(A) There are no legal limits, as there are for cod and haddock, on the size of monkfish that can be caught ….

“(B) There are no legal limits on the size of monkfish that can be caught, unlike cod or haddock ….

“(C) There are legal limits on the size of cod and haddock that can be caught, but not for monkfish ….”

Answer (B) does also use that unlike word to signal the contrast. If you are going to use unlike, then you have to follow the same rules for the word like. You’re comparing nouns (so far, so good, since cod and haddock are both nouns).

The problem with choice (B) is in the structure of the first part about monkfish. The word monkfish is part of a prepositional phrase (of monkfish). You can compare prepositional phrases to prepositional phrases or nouns to nouns—but not a prepositional phrase to nouns. (It’s also a good idea, when using unlike to compare nouns, to have the two sets of nouns closer to each other, by the way.) Eliminate (B).

Answer (C) seems to fix this problem—we have of cod and haddock and for monkfish. Both prepositional phrases!

Why did I say it only seems to fix the problem? When you use the word but to make a contrast, the rules change. The word but is a conjunction. Before the conjunction we have an entire clause (There are legal limits…). After the conjunction, then, we have to have another clause—but we don’t. There’s only the prepositional phrase for monkfish. Eliminate (C). You could fix this part of this choice by saying something like “but there are not for monkfish…”

Okay, time to look at those other two that used the Unlike setup. In this case, the comparison marker comes right at the beginning of the sentence, so the structure should be Unlike X, Y (where X and Y are the elements being compared).

“(D) Unlike cod and haddock, there are no legal size limits on catching monkfish ….

“(E) Unlike catching cod and haddock, there are no legal size limits on catching monkfish ….”

In the case of choice (D), the X element consists of plain nouns (cod and haddock) but the Y element is what comes after the comma: the word there. If we’re going to have cod and haddock as the X element, we need monkfish after that comma.

Answer (E) is similar. The X element is catching cod and haddock, so the Y element should be something like catching monkfish. They do say catching monkfish later in the sentence—but this element needs to be right after the comma, not later on after the main subject and verb (there are) of the sentence.

Eliminate choices (D) and (E). We’re left with choice (A) as the correct answer.

Wait, I thought that sounded funny! It still does, frankly—but that’s because nobody ever speaks this way. It’s absolutely okay, though, to “break up” the contrast and stick what seems to be the second element (cod and haddock) before the first element (monkfish).

If this sounds funny to you, too, make yourself a flash card with the full correct sentence. Also try to write another comparison sentence—with your own topic—that mimics this structure. Put that one on a flash card too. Review until you ingrain into your brain that this sentence structure is okay!

Let’s also see how we could have used the modifier stuff at the end. This time, I’m going to mentally strip out the comparison and focus just on the core plus the modifier.

“(A) There are no legal limits, as there are for cod and haddock, on the size of monkfish that can be caught, a circumstance that contributes to their depletion through overfishing.

“(B) There are no legal limits on the size of monkfish that can be caught, unlike cod or haddock, a circumstance that contributes to depleting them because they are being overfished.

“(C) There are legal limits on the size of cod and haddock that can be caught, but not for monkfish, which contributes to its depletion through overfishing.

“(D) Unlike cod and haddock, there are no legal size limits on catching monkfish, which contributes to its depletion by being overfished.

“(E) Unlike catching cod and haddock, there are no legal size limits on catching monkfish, contributing to their depletion because they are overfished.”

Glance down the start of each modifier. Spot anything?

Choices (A) and (B) both start with a circumstance. That structure allows the modifier to refer to the entire circumstance or situation that was described in the prior clause. We already decided that was fine in answer (A). What about (B)?

Choice (B) might be okay for the same reasons (A) was, though I’m not super happy about two things. First, they now put unlike cod or haddock in between, so I have to think about whether the sentence is referring to the monkfish’s circumstance or the cod / haddock’s circumstance. And that leads me to the second thing I don’t like: them and they. Who is being depleted / overfished? I shouldn’t have to think this hard to figure out that it’s probably the monkfish. Eliminate (B).

(By the way: Now I’m getting an inkling as to why they structured choice (A) the way they did. They wanted to make sure that it was clear that we were talking about the monkfish being depleted, not the other fish. This actually makes sense, now!)

Answers (C) and (D) are similar: Both use a comma-which modifier structure. These modifiers are supposed to refer to the main noun before the comma.

What exactly contributes to its depletion? Not the monkfish itself! Rather, it’s the fact that there are no legal limits on the size that can be caught…that’s what contributes to its depletion! But that whole “fact” is not just a noun in the sentence. I can’t use comma-which to refer to that whole clause. Eliminate (C).

What about choice (D)? Same deal. From a meaning perspective, that modifier should logically refer to the whole situation or action, not just to a noun shortly before the comma, so I can’t use the comma-which setup here. Eliminate (D).

Finally, choice (E) changes to a comma -ing modifier. I know that comma –ing is supposed to refer to the whole clause. So maybe this is okay?

The sentence sounds funny to me, but I think that’s mainly because of two other things. First, we have the incorrect usage of the comparison at the beginning. It also sounds funny because of this: there are no legal size limits on catching monkfish. It’s not totally clear to me that that’s talking about the size of the monkfish themselves (that is, that the limit is on the size of the fish). Maybe it could refer to the size of the catch—i.e., the total number of fish caught?

And again, I’m now realizing why they wrote answer (A) the way that they did—sometimes, it’s necessary to use more words in order to make sure that your meaning is clear. Between choices (A) and (E), choice (A) is much more clear.

Key Takeaways for Processing Hard GMAT Sentence Correction Problems

(1) Sometimes, your first look at the start of the underline in the original sentence won’t tell you anything, but a glance down the start of each answer choice will reveal something useful. Keep an eye out for those opportunities!

(2) When reading the original sentence, your first goal is to understand the meaning and to notice any potential issues. Don’t necessarily dive in the minute you see something that you think might be an issue. Give yourself a chance to see the sentence as a whole (especially on full underlines!) and then choose your solution path based on your own SC strengths. ?

* GMATPrep® questions courtesy of the Graduate Management Admissions Council. Usage of this question does not imply endorsement by GMAC.

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stacey-koprinceStacey Koprince is a Manhattan Prep instructor based in Montreal, Canada and Los Angeles, California. Stacey has been teaching the GMAT, GRE, and LSAT for more than 15 years and is one of the most well-known instructors in the industry. Stacey loves to teach and is absolutely fascinated by standardized tests. Check out Stacey’s upcoming GMAT courses here.