GMAT Sentence Correction: How to Find the Core Sentence (Part 6)

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Manhattan Prep GMAT Blog - GMAT Sentence Correction: How to Find the Core Sentence (Part 6) by Stacey Koprince

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Harder GMAT Sentence Correction questions often have longer underlines and “jumble up” the answer choices. That is, the answers change so significantly that it’s difficult to figure out what’s different about each one—and, therefore, it’s difficult to figure out where to start or how to eliminate wrong answers efficiently. When this happens, what do you do?

We’re going to talk about exactly that today, continuing our series on finding the sentence core. (Start there if you haven’t seen anything in this series yet.)

Then, try this GMAT Sentence Correction problem from the free GMATPrep® practice exams.

* “In contrast to ongoing trade imbalances with China and Japan, the United States trade deficit with Mexico declined by $500 million as a result of record exports to that country.

“(A) In contrast to ongoing trade imbalances with China and Japan, the United States trade deficit with Mexico declined by $500 million as a result of record exports to that country.

“(B) In contrast to ongoing trade imbalances with China and Japan, the United States sold record exports to Mexico, reducing its trade deficit by $500 million.

“(C) When compared with ongoing trade imbalances with China and Japan, the United States sold record exports to Mexico, reducing their trade deficit by $500 million.

“(D) Compared with ongoing trade imbalances with China and Japan, the United States sold record exports to Mexico, reducing the trade deficit by $500 million.

“(E) Compared to ongoing trade imbalances with China and Japan, the United States record exports to Mexico caused a $500 million decline in the trade deficit with that country.”

Our standard GMAT Sentence Correction Process starts with a step to take a First Glance, allowing you the possibility of figuring out quickly one issue that the sentence might be testing.

The First Glance on this problem shows that the entire sentence is underlined—and that clue makes it much more likely that the answer choices will change quite a bit relative to each other. That tells you that the sentence is more likely to test one of the “global” issues that tend to cross large swathes of a sentence: Sentence Structure, Meaning, Modifiers, or Parallelism. (Though it could test other things, too!)

The first glance here also gives one other clue: The first few words of the original sentence are in contrast to. That’s a comparison marker (comparisons are a subset of parallelism), so one potential starting point would be to check that comparison.

Next, you’re going to read the entire original sentence. Since the entire sentence is underlined, pay particular attention to the “core” of the sentence vs. the extra modifiers tacked on top of the core. (We’ll talk about how to do this below.)

Also, as you go, jot down any notes to help you remember what’s there. For instance, the first thing I might jot down is “Comp” to remind me that the sentence begins with a comparison.

Ready? Let’s do this!

In contrast to ongoing trade imbalances with China and Japan, the United States trade deficit with Mexico declined by $500 million as a result of record exports to that country.”

What did you think?

The whole opening part (to the comma) is a modifier—it can’t stand alone as a sentence (i.e., it’s not the sentence core). It does contain that comparison language, though, so if I want to deal with the comparison first, that’s where I’ll focus my attention.

Where is the sentence core, then? It starts after that comma:

“…the United States trade deficit with Mexico declined by $500 million…”

How far do we go? Go as far as you need to in order to have a complete sentence. I don’t need to go any farther than the above. The other part starting as a result does explain why the trade deficit declined, but I don’t need that information in order to have a complete sentence. It’s extra—more modifier.

So now I’m going to think of this sentence as three “chunks”:

First chunk: Comparison marker plus part of the comparison itself

Second chunk: The core sentence, explaining what happened with the US trade deficit with Mexico

Third chunk: Another modifier, explaining why the core sentence stuff happened

My scrap paper might look like this:

Comp    |    Core: what    |    Mod: why

In answers (B), (C), (D), and (E), some of those chunks might move around or change structure. In some cases, information that’s in the core sentence might move to a modifier or vice versa. Now, I’m prepared to notice how those changes occur.

Finally: Did you spot anything about the original sentence that you didn’t like? Is there anything we can tackle right now to eliminate the original sentence?

Part of me is wondering whether you’re supposed to say in contrast to or in contrast with. I’m not entirely sure. Glancing down the answers, I see that (B) also says in contrast to, but the others change to different words: when compared with, compared with, or compared to. The word with has finally made an appearance…but I’m still not sure whether both forms are okay or what—so I’m going to ignore this and look for something else to use instead.

Let’s check the comparison itself. The marker is in contrast to X, Y, where the X and Y portions have to be parallel and the same kind of thing. Are they?

In the original sentence, yes. We’ve got:

“In contrast to ongoing trade imbalances with China and Japan, the United States trade deficit with Mexico…”

Trade imbalances and trade deficit are parallel (both nouns) and they’re the same “kind” of thing—they’re both talking about trade differences between countries.

Check the comparison in the other answers:

“(B) In contrast to ongoing trade imbalances…, the United States sold…

“(C) When compared with ongoing trade imbalances…, the United States sold…

“(D) Compared with ongoing trade imbalances…, the United States sold…

“(E) Compared to ongoing trade imbalances…, the United States record exports to Mexico caused…”

Answers (B), (C), and (D) all have the same problem: they compare trade imbalances to the country of the United States. Those aren’t the same kind of thing, so they can’t be compared to each other. All three of these can be eliminated for making a faulty comparison.

What about answer (E)? This one compares trade imbalances to exports. This is certainly better than comparing trade imbalances to an entire country. It’s still not quite the same kind of thing, though. They’re related: A country can have record exports that result in a trade imbalance or record exports that result in balanced trade. But the record exports themselves are not the same idea as a trade imbalance—rather the trade deficit is the same kind of idea as a trade imbalance.

Hey—where is the trade deficit in answer (E)? Did they remove it?

No, they didn’t—the trade deficit does appear later in the sentence. So the best thing would be to put that after the comma so that you can directly compare the trade imbalances in 2 countries with the trade deficit in a 3rd country.

Eliminate answers (B), (C), (D), and (E) for a faulty comparison. The correct answer is (A).

We were able to solve that without dealing with all those changing chunks, especially towards the end of the sentence! So why did I choose this as an example of dealing with answers that change a lot?

I chose it because the test writers are hoping to distract you with those changing answers—possibly to get you to fall into a trap and get this one wrong. (And, at the very least, they’re hoping to get you to spend way too much time trying to answer this one.)

The first glance gave us a clear issue: there’s a comparison going on. If you feel comfortable dealing with comparisons, go for it! Then you won’t have to worry about the more annoying changes occurring later in the sentence, most of which are actually fine.

Key Takeaways for Full Underlines in GMAT Sentence Correction

(1) Much of the time, full underlines test at least one of Sentence Structure, Meaning, Modifiers, and Parallelism—in this case, the problem tested Comparisons, a subset of Parallelism. Still use your First Glance to spot major markers that can tell you what’s going on.

(2) If you do need to deal with significant changes in “chunks” of the answer choices, you will—but don’t get so distracted by those changes that you miss clues sitting right in front of you.

(3) Comparisons require the X and Y portions to be parallel (that is, in the same form, such as noun to noun or prepositional phrase to prepositional phrase). They also require the X and Y elements to be the same kind of thing: a country to a country, for example, or (as in this case) a type of trade issue to a type of trade issue. ?

Read on for Part 7 of How to Find the Core Sentence here!

* 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.