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Sentence Correction: Parallelism Questions - Overview

Concerned about the dangers posed to civil aviation by migratory birds, the national aviation administration and several wildlife protection societies have collaborated in a project aimed at monitoring flight patterns of high-flying species such as storks, herons, and geese, tightening coordination of landing and take-off times of commercial air traffic, and the training of pilots to avert and prevent collisions.   

Incorrect.

This answer choice is grammatically incorrect. The first two items in the list of the sentence are unconjugated verbs (monitoring, tightening), but the last item is a noun (the training). What is tricky about this list is that the noun the training has the same form as the verbs, but because of the article the (training), the V+ing form functions as a noun, and violates the parallelism.

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Incorrect.

This answer choice repeats the Parallelism mistake in the original question, and even creates another Parallelism mistake mistake, resulting in an illogical sentence.

In the corrected sentence, the modifier aimed is changed to a V+ing form aiming and the first verb in the list is changed to a to V form to monitor. As a result, the already faulty parallelism of the original list of the project's aims is damaged even more because the second and third items (tightening, the training of) are still in Ving form and are different parts of speech (tightening = verb; the monitoring of = noun)

Even if aiming (and not to monitor) is seen as the first item in the parallelism, logical or grammatical problems remain. The original sentence presents a list of the aims of the collaborative project. Therefore it is not logical for aiming to be included as one of the items in the list. The resulting sentence is also grammatically incorrect: one cannot say aiming tightening coordination...and aiming the training of pilots.

Well done!

This answer choice corrects the Parallelism mistake in the original question, by changing the noun the training to a non-conjugated verb training, to match the previous items in the list (monitoring, tightening coordination).

[[snippet]]

What's tricky about this list is that the noun the training has the same form as the verbs, but because of the article the (training), the V+ing form functions as a noun, and violates the parallelism.

Although this answer choice is not stylistically perfect (avert and prevent is a redundancy, as these two words mean approximately the same thing), it is the only answer choice that is grammatical, logical, and has a correct parallel structure. 

Incorrect.

This answer choice is grammatically incorrect.

[[snippet]]

The original sentence has a list of three non-parallel items: monitoring (V+ing verb), tightening (V+ing verb), the training (V+ing noun). 

In the corrected sentence, the modifier aimed is changed to a V+ing form aiming and the first and third items in the list are changed to a to V form to monitor//to train. However, the second item tightening (V+ing) is not parallel to them.

Reading the sentence as if aiming (and not to monitor) were the first item in the parallelism doesn't solve the problem, either logically or grammatically. The original sentence presents a list of the aims of the collaborative project. Therefore it is not logical for aiming to be included as one of the items in the list. The resulting sentence is also grammatically incorrect: one cannot say aiming tightly coordinating.

In addition, changing the noun phrase landing and take-off times to a clause when commercial air traffic is to take off and land is awkward and wordy.

Incorrect.

This answer choice is illogical, and it doesn't fit into the original sentence.

[[snippet]]

This answer choice appears to correct the Parallelism mistake in the original question, but the three actions are not logically parallel. The original sentence presents a list of the aims of the collaborative project. Therefore it is not logical for to aim to be included as one of the items in the list. The three logically parallel actions in this sentence are: monitoring, coordinating, training. To aim at only serves as the introduction to the three items which should be parallel.

In addition, the addition of the word but makes little sense because but usually shows an opposition or negation to something previously stated. In this case the three items in the list are meant to be aims of the project and no opposition exists among the aims stated.

aimed at monitoring flight patterns of high-flying species such as storks, herons, and geese, tightening coordination of landing and take-off times of commercial air traffic, and the training of pilots to avert
aiming to monitor flight patterns of high-flying species such as storks, herons, and geese, tightening coordination of landing and take-off times of commercial air traffic, and the training of pilots to avert
aimed at monitoring flight patterns of high-flying species such as storks, herons, and geese, tightening coordination of landing and take-off times of commercial air traffic, and training pilots to avert
aiming to monitor flight patterns of high-flying species such as storks, herons, and geese, tightly coordinating when commercial air traffic is to take off and land, and to train pilots to avoid
to aim at monitoring flight patterns of high-flying species such as storks, herons, and geese, to coordinate tight landing and take-off times for commercial air traffic, but to train pilots to avert