Dangling Modifiers on the GMAT

Properly identifying incorrect modifier constructions, which are common errors in Sentence Correction, is a key component in achieving a high score on the GMAT. Knowing that modifier errors are among the most common errors seen on the GMAT, the astute student carefully studies the rules of correctly using modifiers. These grammatical constructions, among the most difficult to spot at a glance, confuse students and frustrate test takers who haven’t adequately prepared for the exam.

Modifiers on the GMAT can take many forms, but the most common ones are used correctly above. (Did you notice the plethora of modifiers in the above paragraph?) Multiple kinds of modifier errors, in which an element modifying a part of the sentence is used incorrectly, show up regularly in Sentence Correction. However, the type I want to highlight is one of the GMAT’s favorite tricks: the dangling modifier (cue the song “My Favorite Mistake”).

Consider the following sentence in a vacuum: “Alarmed by the recent decline of the stock market, many retirement investments have been switched from stocks to more conservative options, such as money market funds.” Logically, I understand what is being said here. The stock market is in decline and investments are being transferred to less risky alternatives. However, the sentence begins with the modifier “Alarmed by xyz,” which means that whatever follows the comma must be alarmed. In this case, the subject of the sentence would be retirement investments, but can investments be alarmed? (Even if they’re Blackberry stock, it’s unlikely).

Since investments cannot be alarmed, the subject must be changed to a term that can be alarmed. In other words, the subject of the modifier needs to be someone who is capable of actually being alarmed. Someone like an investor, a hedge fund manager or even just a nonspecific person. We can rewrite this phrase as “Alarmed by the recent decline of the stock market, many investors have switched their retirement investments from stocks to more conservative options, such as money market funds.” This minor change shrewdly fixes the dangling modifier issue present in the previous version and creates a perfectly correct (or cromulant) sentence.

These types of errors show up all over Sentence Correction problems. Let’s look at an example of a dangling modifier:

Knowing that the area was prone to earthquakes, all the buildings were reinforced with additional steel and concrete.

(A)   Knowing that the area was prone to earthquakes,

(B)   Having known that the area was prone to earthquakes,

(C)   Since the area was known to be prone to earthquakes,

(D)   Since they knew that the area was prone to earthquakes,

(E)    Being prone to earthquakes,

Since the entire participial phrase “Knowing that the area was prone to earthquakes,” must logically modify the noun after the comma, it becomes fairly clear that A cannot be the correct answer. After all, buildings may be sturdy and resistant to wind, but they cannot possibly know which areas are under tectonic plates (Skynet’s new plan may involve intelligent buildings?). The participial phrase is what’s underlined here, which means we need to replace it with something that refers to the buildings, or else rewrite it entirely. Either way, answer choice A makes a classic dangling modifier error.

Answer choice B “Having known that the area was prone to earthquakes” introduces the same error to the sentence. The buildings are not the ones that knew about the earthquakes, regardless of the tense of the verb. Answer choice B can be quickly eliminated.

Answer choice C mixes things up a little by stating “Since the area was known to be prone to earthquakes,”. This provides a plausible causal effect for the rest of the sentence without putting the onus solely on the buildings. This formulation is devoid of any modifier errors, and there are no other glaring errors, so it should be the correct answer. We should review the other two choices to ensure we can eliminate them for valid reasons, but C should be the answer once the dust settles (pun intended)

Answer choice D “Since they knew that the area was prone to earthquakes,” removes the dangling modifier error, but simultaneously creates a new pronoun error. Who is being referred to with the pronoun “they”? It could be the buildings, or it could be someone else entirely, perhaps even a team of civil engineers (or perhaps the Seattle Seahawks). The ambiguity will eliminate this answer choice from being the correct choice.

Answer choice E succinctly proposes “Being prone to earthquakes,” which now changes the meaning of the sentence to indicate that the buildings are prone to earthquakes. The area has been completely removed (like removing a dimension from a square). Answer choice E changes the meaning to an illogical construction and can therefore be promptly eliminated as well.

Answer choice C was indeed the correct choice on this question. Since language is somewhat subjective, it’s possible to have multiple constructions that are all grammatically correct. As such, if one answer choice does not have any errors, it will be the correct answer choice. Sentence correction is very much a process of elimination, and easily identifying dangling modifier errors will help you eliminate incorrect answer choices quickly.

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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.