Learn the 4 Things You Must Know Before Taking the GMAT!   Download it Now!

GMAT Sentence Correction Tip: Take Clues from the Un-Underlined Portion of the Sentence

Confirmation Bias - GMAT Sentence CorrectionsThere’s a marketing terms that you’ll learn about in business school called confirmation bias. It refers to the phenomenon in which your mind subconsciously looks for evidence to support a decision you’re on the verge of making. In other words you have a certain bias, something you believe to be true or a decision you plan to make, and then your mind goes to work to confirm that belief or decision by looking externally for confirmation. It’s like when you decide you want to buy a red Mercedes convertible, and the next thing you know you start seeing them all over the road!

On GMAT sentence correction questions, this bias can get you into trouble.

The Power of the Un-Underlined Words in a GMAT SC Sentence

A lot of students focus too heavily on the underlined portion of the sentence in GMAT sentence corrections. In other words they’re biased, and they miss some objective truths elsewhere as a result. If there’s going to be a mistake in the sentence after all, it’s going to be in the underlined portion of the sentence, right? I mean, that’s what the directions say, don’t they?

Yet often the clues for what’s wrong with the sentence lie outside the underlined portion. If your confirmation bias leads you to spend too much effort and attention focusing just on the underlined portion, you might miss crucial evidence that will lead you to the right answer.

GMAT Tip: In GMAT Sentence Correction questions, often the un-underlined portion of the sentence dictates what must change in the underlined portion.

Consider this example from the GMAT Review Official Guide, 13th ed. (p.685 #75):

More and more in recent years, cities are stressing the arts as a means to greater economic development and investing millions of dollars in cultural activities, despite strained municipal budgets and fading federal support.

(A) to greater economic development and investing
(B) to greater development economically and investing
(C) of greater economic development and invest
(D) of greater development economically and invest
(E) for greater economic development and the investment of

Your tendency may be to only focus on the underlined portion of the sentence since that’s where the error has to be (if there is one), right? Toward that end, you may be inclined to think that parallel construction rules (see “Sentence Correction – Part 2”) would dictate that investing be changed to investment to match development, which would lead your eye to answer choice E. But that’s not correct. In this example, there’s actually an idiom error. The only way you would pick up on that would be if you were mentally tuned in to the words outside of the underlined portion of the sentence as well. The words “…as a means…” should cause a mental trigger based on your knowledge of common GMAT idioms that the phraseology “…as a means TO…” is incorrect. It should idiomatically be “…as a means OF….”

So, at this point you can quickly eliminate all but answer choices C and D which use that idiom correctly. For wordiness reasons, you can then eliminate answer choice D. Answer choice C is correct.

Parallel Construction Application

Let’s take a look at another example from the GMAT Review Official Guide (p. 694 #121) that illustrates the importance of the un-underlined portion of the sentence:

New theories propose that catastrophic impacts of asteroids and comets may have caused reversals in the Earth’s magnetic field, the onset of ice ages, splitting apart continents 80 million years ago, and great volcanic eruptions.

(A) splitting apart continents
(B) the splitting apart of continents
(C) split apart continents
(D) continents split apart
(E) continents that were split apart

GMAT SC Parallel ConstructionHopefully you quickly picked up on the fact that we have a list in this sentence of the things “asteroids and comets may have caused.” And things in a list, as you know, must be expressed in parallel grammatical fashion (i.e. the same structure using the same pattern of words) to show that the listed words or ideas are of equal importance and to help the reader comprehend what is being written.

In general, the things in the list can be expressed in just about any grammatical form provided they’re the same. For example, saying “I like golf, soccer, and tennis” (noun form) is equally correct as saying “I like golfing, playing soccer, and playing tennis” (gerund form).

So how do you choose? How do you know which form will be preferred by the makers of the GMAT?

Look to the un-underlined portion of the sentence for clues.

In the example above, each of the effects of catastrophic impacts of asteroids and comets is given in noun form (reversals, the onset, eruptions) EXCEPT the one included in the underlined portion (splitting). Splitting is a verb (gerund) and thus not parallel to the other nouns in the series. In theory, the other three effects could be changed to the verb form to match splitting, but of course that’s not allowed because the un-underlined portion of the sentence is effectively locked in stone and can’t be altered. As such, the un-underlined portion dictates what else must change in the sentence which requires splitting to be changed to the splitting to make it a noun and thus parallel with the other three items in the list.

The correct answer, therefore, is B. Great job if you got that!

Granted, this isn’t an overly difficult example but the underlying truth it teaches — namely that you can take clues from the un-underlined portion of the sentence to figure out what must change in the underlined portion — is an important one for you to internalize because it will help you on more difficult GMAT sentence correction questions as well.

By the way, what’s an example of confirmation bias that you’ve experienced in your own life? Share your story in the comment box below!