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In this article, we’ll work through a standard GMAT sentence correction question that involves comparisons using an Official Guide to the GMAT diagnostic exam practice problem. You can either read this article or watch this GMAT sentence correction video on YouTube.
GMAT Sentence Correction Practice Question from GMAC
Unlike the buildings in Mesopotamian cities, which were arranged haphazardly, the same basic plan was followed for all cities of the Indus Valley: with houses laid out on a north-south, east-west grid, and houses and walls were built of standard-size bricks.
(A) the buildings in Mesopotamian cities, which were arranged haphazardly, the same basic plan was followed for all cities of the Indus Valley: with houses
(B) the buildings in Mesopotamian cities, which were haphazard in arrangement, the same basic plan was used in all cities of the Indus Valley: houses were
(C) the arrangement of buildings in Mesopotamian cities, which were haphazard, the cities of the Indus Valley all followed the same basic plan: houses
(D) Mesopotamian cities, in which buildings were arranged haphazardly, the cities of the Indus Valley all followed the same basic plan: houses were
(E) Mesopotamian cities, which had buildings that were arranged haphazardly, the same basic plan was used for all cities in the Indus Valley: houses that were
As is the case with every GMAT strategy, the first step is to set up your scratch pad.
To avoid confusion down the line, write down the question number first. Next, write the corresponding letters for each answer choice in a vertical line so you can easily mark them as you work through the process of elimination. Finally, draw a line to designate the space in which you will articulate the particular issue you will later identify within the sentence so that you don't lose sight of it as you work through the problem.
Now that your scratch pad is set up, it’s time to read the sentence.
In this case, the use of the term “unlike,” indicates a comparison between “the buildings in Mesopotamian cities” and “the same basic plan.” Because cities and plans are not conceptually comparable, the issue within this particular sentence is a comparison type error—critical information which you can now write within the blank line you drew on your scratch pad. Once the error type has been identified, you may proceed to analyze your answer options.
Because choice A is always the original sentence as written, we can eliminate that immediately.
Choice B once again compares “the buildings in Mesopotamian cities” with “the same basic plan,” so we can eliminate that as well.
Although it’s slightly different from the previous answers, choice C compares “the arrangement of buildings” with the “cities of the Indus Valley,” which still represents a comparison error. For this reason, C can also be eliminated with confidence. (Note that you should always evaluate your choices by seeking the same category of error, not just the exact same language.)
Choice D compares “Mesopotamian cities” with “cities of the Indus Valley.” Because cities are conceptually comparable, this is the correct answer.
The final option, which compares “the same basic plan” and “Mesopotamian cities,” presents the same flaw as the other incorrect answers, and can also be eliminated with certainty.
Conclusion
So there you have it. The correct answer is D because it is the only option that resolves the comparison type error present in the original sentence.
We hope this example was helpful! To see all of our GMAT sentence correction videos, please check out our YouTube playlist. For further information about MyGuru's proven GMAT tutoring approach, visit the GMAT prep page on our website. To learn more about the GMAT and grad school admissions in general, visit our GMAT admissions blog. Happy studying.
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