GMAT Sentence Correction: Parallelism for Postgraduate Success

GMAT Sentence Correction: Parallelism Mastery

What the Examiner is Testing

The GMAT Sentence Correction section assesses your ability to identify and rectify grammatical errors, particularly focusing on logical consistency and stylistic elegance. For parallelism, the examiner is testing your understanding of how to construct grammatically balanced sentences when listing items, comparing elements, or expressing sequential actions.

The Method

Follow these numbered steps consistently to tackle parallelism questions effectively:

1. Identify the Core Structure: Scan the sentence for conjunctions like "and," "or," "but," "rather than," "as well as," or correlative conjunctions such as "either...or," "neither...nor," "not only...but also," "both...and." These are strong indicators that parallelism is required.
2. Locate the Parallel Elements: Once you've identified the conjunction, pinpoint the elements it connects. These elements must be grammatically equivalent. For example, if one element is a noun, the other(s) must also be nouns; if it's an infinitive phrase, the other(s) must be infinitive phrases.
3. Check for Grammatical Consistency: Ensure that the identified parallel elements share the same grammatical form. This includes verb tense, voice, part of speech, and phrase structure.
4. Evaluate for Logical Consistency: Beyond grammar, the parallel elements must also make logical sense in their relationship. Sometimes, grammatically parallel structures can still be illogical.
5. Test Each Option (if applicable): If it's a multiple-choice question, apply steps 1-4 to each answer choice. Eliminate options that violate parallelism or introduce other grammatical errors.
6. Select the Most Concise and Clear Option: Among grammatically and logically correct options, choose the one that is most concise and expresses the intended meaning clearly without redundancy.

Fully Worked Example

Original Sentence: The company's strategy involved reducing overhead costs, to improve operational efficiency, and they wanted to expand market share.

Let's apply our method:

1. Identify the Core Structure: The key conjunction here is "and," connecting three elements in a list.
2. Locate the Parallel Elements:
   • Element 1: "reducing overhead costs" (gerund phrase)
   • Element 2: "to improve operational efficiency" (infinitive phrase)
   • Element 3: "they wanted to expand market share" (independent clause)
3. Check for Grammatical Consistency: We immediately see a breakdown in parallelism. We have a gerund phrase, an infinitive phrase, and an independent clause. These are not grammatically consistent.
   • To make them parallel, we need to transform all elements into the same grammatical form. Let's aim for gerund phrases, as the first element already uses one.
     • Element 1: "reducing overhead costs" (already a gerund phrase)
     • Element 2 (transformed): "improving operational efficiency" (gerund phrase)
     • Element 3 (transformed): "expanding market share" (gerund phrase)
4. Evaluate for Logical Consistency: The three actions (reducing costs, improving efficiency, expanding share) are all logical components of a company's strategy.
5. Test Each Option (Hypothetical):
   • Option A (Original): Fails due to grammatical inconsistency.
   • Option B: The company's strategy involved reducing overhead costs, improving operational efficiency, and expanding market share. (All gerund phrases – grammatically consistent and logical).
   • Option C: The company's strategy involved reducing overhead costs, to improve operational efficiency, and market share expansion. (Still inconsistent: gerund, infinitive, noun phrase).
6. Select the Most Concise and Clear Option: Option B is grammatically parallel, logically sound, and concise.

Corrected Sentence: The company's strategy involved reducing overhead costs, improving operational efficiency, and expanding market share.

Three Mistakes That Lose Marks on This Topic

1. Ignoring the "Hidden" Parallelism: Students often focus only on obvious lists. However, parallelism is also critical in comparisons (e.g., "rather than," "as...as") and with correlative conjunctions (e.g., "not only...but also"). Missing these less overt structures leads to errors. For instance, "She prefers running rather than to swim" is incorrect; it should be "She prefers running rather than swimming."
2. Mismatched Grammatical Forms: This is the most common error. Parallel elements must be of the same grammatical type. A common mistake is mixing verb forms (e.g., "to run, jumping, and walked"), noun forms (e.g., "a book, an apple, and reading"), or phrase types (e.g., "by studying hard, by taking notes, and because she was diligent"). The GMAT often uses subtle variations to trick test-takers, such as switching between gerunds and infinitives.
3. Breaking the "Rule of Three" (or more): When dealing with three or more items in a list, ensure that all items are parallel, not just the first two. Examiners frequently create options where the first two items are parallel, but the third (or subsequent) item breaks the pattern. Always check every element connected by the conjunction.

30-Second Recap

Parallelism demands grammatical and logical consistency among connected elements, often indicated by conjunctions. Use a systematic approach: identify the conjunction, pinpoint the elements, ensure grammatical and logical consistency, and then choose the most concise option. Avoid mismatched forms, overlooking correlative conjunctions, and failing to check all elements in a list. Master this, and you'll significantly boost your GMAT Sentence Correction score.