How to Attack GMAT Sentence Correction Questions Like a Boss

Many people think that finishing the GMAT verbal section on time hinges on quickly solving Sentence Correction problems. This is because these questions tend to have the shortest stimuli of any question type. Even if you’re a speed reader (hopefully you never ordered Mega Reading by Kevin Trudeau), it will still take a minute or so to sift through a passage that’s a few hundred words long. Sentence Correction problems sometimes have stimuli that are two or three lines, and therefore are prime candidates for quick dispatching.

However, sometimes you encounter Sentence Correction passages that are as long as paragraphs. Your job is the same no matter the length of the text, but Sentence Correction problems require you to evaluate every decision point among the answer choices. The longer the sentence, the more decision points you may have to consider. The number of false decision points also tends to increase as the sentence length increases. False decision points are differences between answer choices in which both options are acceptable, so making a choice based on such a decision point could erroneously eliminate a valid answer choice. Indeed, picking between an alternative and a substitute is an exercise in futility.

Another issue that comes up is mental fatigue. Conventional grammatical wisdom postulates that sentences longer than 20-25 words begin to lose their effectiveness, as the human brain struggles to process all the information. Run-on sentences can cause readers to disengage as they find themselves apathetic to the point that the author is trying to make. Often students report a lack of interest on longer passages, and an increased urge to simply select an answer choice (sometimes at random) to move on to a different question.

Let’s look at an example, which clocks in at an impressive 51 words.

The first trenches that were cut into a 500-acre site at Tell Hamoukar, Syria, have yielded strong evidence for centrally administered complex societies in northern regions of the Middle East that are arising simultaneously with but independently of the more celebrated city-states of southern Mesopotamia, in what is now southern Iraq.

(A)   that were cut into a 500-acre site at Tell Hamoukar, Syria, have yielded strong evidence for centrally administered complex societies in northern regions of the Middle East that are arising simultaneously with but

(B)   that were cut into a 500-acre site at Tell Hamoukar, Syria, yields strong evidence that centrally administered complex societies in northern regions of the Middle East were arising simultaneously with but also

(C)   having been cut into a 500-acre site at Tell Hamoukar, Syria, have yielded strong evidence that centrally administered complex societies in northern regions of the Middle East were arising simultaneously but

(D)   cut into a 500-acre site at Tell Hamoukar, Syria, yields strong evidence of centrally administered complex societies in northern regions of the Middle East arising simultaneously but also

(E)    cut into a 500-acre site at Tell Hamoukar, Syria, have yielded strong evidence that centrally administered complex societies in northern regions of the Middle East arose simultaneously with but

The first thing you might notice is that, not only is this sentence way too long, most of it is underlined. That means it will take a fair amount of time just to peruse the answer choices. Our best strategy will probably not be to read through the five similar answer choices without any specific goal.

With run-on sentences, you want to be methodical and review each decision point as it comes up. As noted before, some may be false decision points and you cannot eliminate any choice. However, some words are low hanging fruit, such as verbs or pronouns, which have to be in specific forms (i.e. singular vs. plural). Connectors to and from the underlined portion are often significant as well, since they serve as springboards from one section to the next.

Looking at the original sentence (answer choice A) and going through the words, we’re looking for verbs and pronouns that can help guide our decisions. The first verb encountered is “were cut”, but the verb cut is tricky because it has the same form in the past, the present and the future. Answer choice C’s “having been cut” seems unnecessarily wordy, but that is not necessarily enough to eliminate it outright, so we’ll keep it with an asterisk and continue looking for other verbs.

The next verb encountered is “have yielded”, and a cursory comparison of the other answer choices reveals a 3-2 split between “have yielded” and “yields”. The subject of the verb is “The first trenches”, which is plural. The verb formulation of “yields” only works if the subject is singular, and thus we can eliminate these answer choices with 100% certainty as they contain agreement errors. Answer choices B and D can both be eliminated.

Continuing on, the second verb we encounter is “are arising”. Everything else about specific locations, sizes of land and other minutiae can be ignored using the slash-and-burn technique. We’re on a mission to compare specific terms that can help illuminate errors in various answer choices. Answer choice C has “were arising” and answer choice E has “arose”. The subject of the verb is “societies”, and therefore any of the three could be correct from an agreement standpoint. However, the timelines vary from present to past continuous to simple past, and the rest of the sentence began with the past-tense verb “have yielded”, meaning that the present tense would be erroneous. Answer choice A can be eliminated because of a timeline error.

At this point, only answer choices C and E remain. The verbs are not identical in the two options, but either one could conceivably make sense, so we must look for other differences in order to differentiate between the two. Looking through the answer choices, there are no pronouns to compare, but the first and last words are not the same. These connectors often cause answer choices to be eliminated because they make sense with the underlined portion but they do not fit nicely into the rest of the sentence (like merging onto the highway on a horse and buggy).

Answer choice C is already on our radar because of the wordy verb choice, but let’s examine how it fits back into the sentence at the end. The societies “were arising simultaneously…” is missing the word “with” in order to make grammatical sense. You arise simultaneously with something else. The original sentence had this word, but answer choice C omits the key words, and it’s difficult to see because the text is so verbose. This incorrect construction dooms answer choice C. Only answer E remains as the correct choice.

As with any Sentence Correction question, process of elimination is the name of the game. However, when the sentences get very long, very technical, or otherwise disengaging, you have to go through the text in a methodical manner. The best words to compare are the verbs, the pronouns and the connectors to and from the underlined portion. If you have a sound strategy, you’ll be able to execute the run on sentence correction.

Plan on taking the GMAT soon? We have GMAT prep courses starting all the time. And, be sure to find us on Facebook and Google+, and follow us on Twitter!

Ron Awad is a GMAT instructor for Veritas Prep based in Montreal, bringing you weekly advice for success on your exam.  After graduating from McGill and receiving his MBA from Concordia, Ron started teaching GMAT prep and his Veritas Prep students have given him rave reviews ever since.