Digital SAT Writing: Parallel Structure

Parallel structure is the grammatical principle that gives your writing clarity, rhythm, and professional polish. On the Digital SAT, it's a frequently tested concept that assesses your ability to spot and correct inconsistencies in sentence construction. Mastering parallel structure—which requires matching grammatical forms for items in lists, comparisons, and paired constructions—is not just about passing a test; it's about learning to communicate with precision and impact in any academic or professional setting.

What is Parallel Structure?

Parallel structure (or parallelism) is the practice of using the same pattern of words or grammatical form to show that two or more ideas have equal importance. Think of it as the grammatical equivalent of balance. Just as you wouldn’t wear one formal shoe and one sneaker, you shouldn’t mix a noun with a verb phrase when presenting a coordinated list. This principle applies to any elements joined by coordinating conjunctions (like and, or, but) or correlative conjunctions (like not only…but also, either…or). The core rule is simple: items that are linked must be of the same grammatical type. On the SAT, a question testing parallelism will present a sentence with an underlined portion containing a list or comparison. Your task is to identify the option that makes all the coordinated elements match.

Parallel Structure in Lists: Nouns, Verbs, and More

The most common parallel structure questions involve lists or series. All items in the list must share the same grammatical identity.

• Parallel Nouns: Incorrect: Her backpack contained a textbook, notebooks, and to write with pens. Correct: Her backpack contained a textbook, notebooks, and pens.

The incorrect version mixes nouns ("a textbook," "notebooks") with an infinitive phrase ("to write with pens"). The correct version uses all nouns.

• Parallel Verbs: Incorrect: On weekends, he enjoys hiking, to cook, and reading. Correct: On weekends, he enjoys hiking, cooking, and reading.

Here, all items must be gerunds (verbs ending in -ing functioning as nouns) to be parallel objects of the verb "enjoys."

The key is to identify the lead-in to the list and ensure every item fits grammatically. A good test is to read each list item separately with the lead-in: "he enjoys hiking," "he enjoys to cook," "he enjoys reading." The mismatched item ("to cook") becomes obvious.

Parallel Phrases and Clauses

Parallelism becomes trickier—and more frequently tested—when the items in a series are longer phrases or entire clauses. The same rule applies: their structures must mirror each other.

• Parallel Prepositional Phrases: Incorrect: She looked for her keys in the kitchen, under the couch, and checked the car. Correct: She looked for her keys in the kitchen, under the couch, and inside the car.

The first two items are prepositional phrases ("in...", "under..."); the third must also be a prepositional phrase ("inside...").

• Parallel Clauses: Incorrect: The instructor explained that the lab was mandatory and we should be on time. Correct: The instructor explained that the lab was mandatory and that we should be on time.

Including the second "that" creates parallel noun clauses. While sometimes optional in standard writing, the SAT often requires this explicit parallelism for clarity.

Parallelism in Comparisons and Paired Constructions

Beyond simple lists, parallelism is crucial in sentences that set up a direct comparison or use specific paired conjunctions.

• Comparisons (using than or as): Incorrect: Reading the novel was more enjoyable for me than to watch the film adaptation. Correct: Reading the novel was more enjoyable for me than watching the film adaptation.

The items being compared ("Reading..." and "watching...") must be in the same form.

• Correlative Conjunctions (e.g., not only…but also, either…or, both…and): These word pairs must be followed by parallel elements.

Incorrect: The strategy was not only innovative but also it was cost-effective. Correct: The strategy was not only innovative but also cost-effective. The words following "not only" ("innovative," an adjective) and "but also" ("cost-effective," an adjective) are now parallel. Another correct version could be: Not only was the strategy innovative, but it was also cost-effective, where the clauses following each part are parallel.

Advanced Applications and SAT Strategy

Some of the most challenging SAT questions involve parallelism within complex sentences. Pay close attention to the overall sentence architecture.

• Parallelism in a Series within a Larger Structure:

Incorrect: The company pledges to reduce waste, to conserve energy, and that it will invest in renewable resources. The first two items are infinitive phrases ("to reduce," "to conserve"); the third is a noun clause ("that it will invest"). To fix it, make the third item an infinitive phrase: ...and to invest in renewable resources.

• The "Lead-Word" Test: This is your best strategic tool on the exam. When you see a list or paired construction, identify the word or phrase that introduces the first item. Every subsequent item must be able to logically and grammatically follow that same lead word.
• Example: "She is known for her dedication, her creativity, and her innovative solutions."
• Lead word: for her.
• Test: for her dedication (✓), for her creativity (✓), for her innovative solutions (✓). All pass. If the last item were "for being innovative," the test would fail: "for her for being innovative" is illogical, revealing the fault.

Common Pitfalls

1. Mixing Gerunds and Infinitives: This is a classic trap. An infinitive ("to run") and a gerund ("running") are not parallel forms. Incorrect: His goals are to graduate, finding a job, and to travel. Choose one form and stick with it.

1. Shifting Between Active and Passive Voice: Items in a series should maintain a consistent voice. Incorrect: The proposal was drafted by the committee, reviewed by legal, and the CEO approved it. The last item is active voice, breaking the parallel passive structure of the first two.

1. Faulty Comparisons with "Than" or "As": Ensure you are comparing like with like. Incorrect: The works of Shakespeare are often studied more than Jane Austen. This incorrectly compares "works" to "Jane Austen." Correct: The works of Shakespeare are often studied more than those of Jane Austen.

1. Ignoring the Logic of Correlative Conjunctions: The grammatical element immediately following the first part of the pair (not only) must match the element following the second part (but also). If a preposition follows "not only," one must also follow "but also."

Summary

• Parallel structure demands that items in a list, comparison, or paired construction share the same grammatical form (all nouns, all gerunds, all infinitive phrases, all clauses, etc.).
• On the Digital SAT, carefully examine any underlined series or comparisons. Use the "lead-word" test to check each item's grammatical consistency.
• Pay special attention to correlative conjunctions like not only…but also and comparisons using than or as, as they are common sources of faulty parallelism.
• The most frequent errors involve mixing gerunds and infinitives, shifting between active and passive voice, and creating illogical comparisons. By making parallelism a conscious part of your editing process, you'll craft clearer, stronger, and more correct sentences.