What Is Parallelism?
Parallelism means keeping the form of words or phrases consistent within a sentence. On the SAT®, parallel structure helps ideas sound clear, logical, and balanced. When related ideas follow the same grammatical pattern, readers can understand them more easily. SAT parallel structure questions often test whether verbs, nouns, or phrases match in form. If one part of a list or comparison changes structure, the sentence becomes awkward or unclear. Recognizing parallelism for SAT success helps you quickly spot these errors.
Types of Parallelism Questions on the SAT
Parallelism SAT questions usually ask you to identify whether related ideas in a sentence follow the same grammatical structure. These questions test clarity, logic, and consistency rather than vocabulary. On the SAT, parallel structure errors often appear in lists, paired ideas, and comparisons. Understanding the common patterns makes SAT parallel structure questions much easier to solve.
Parallel Lists (Series)
Parallel lists present three or more items that should all follow the same grammatical form. On the SAT, every item in a series must be a noun, a verb, or a phrase that matches the others. If one element shifts form, the sentence becomes unbalanced. Parallelism for SAT success depends on spotting these small but important inconsistencies. These questions often appear in writing passages and answer choices.
Examples:
Incorrect: The course focuses on analyzing data, writing reports, and how to present findings.
Correct: The course focuses on analyzing data, writing reports, and presenting findings.
Incorrect: She enjoys to swim, running, and biking.
Correct: She enjoys swimming, running, and biking.
Parallel Phrases & Clauses (Connected With Conjunctions)
When ideas are joined by conjunctions like and, or, but, or not only…but also, the grammatical structure on both sides must match. SAT parallel structure questions frequently test paired verbs, phrases, or clauses connected this way. If one side uses a verb phrase, the other side should do the same. Keeping both sides balanced improves clarity and sentence flow. These errors are easy to miss unless you compare both parts carefully.
Examples:
Incorrect: The coach asked the team to practice harder and that they should arrive early.
Correct: The coach asked the team to practice harder and to arrive early.
Incorrect: The project requires planning carefully but you must execute quickly.
Correct: The project requires planning carefully but executing quickly.
Parallel Comparisons (Than, As…As, Like)
Parallel comparisons compare similar ideas and require matching grammatical forms. On the SAT, words like than, as…as, and like signal that parallel structure is required. Both sides of the comparison must be logically and grammatically similar. If one side is a noun, clause, or verb phrase, the other side should match it. These parallelism SAT errors often affect meaning as well as grammar.
Examples:
Incorrect: The new policy is more effective than the company used last year.
Correct: The new policy is more effective than the one the company used last year.
Incorrect: Running a marathon is as challenging as to climb a mountain.
Correct: Running a marathon is as challenging as climbing a mountain.
If you want guided lessons that break down SAT parallel structure questions step by step, a comprehensive SAT prep course can help you practice these patterns in realistic test scenarios.
Common Mistakes & Traps in SAT Parallelism Questions
Parallelism errors on the SAT are often subtle and designed to test attention to structure rather than meaning. These mistakes usually appear in sentences that sound mostly correct but contain small grammatical mismatches. Knowing the most common traps helps you spot errors faster in SAT parallel structure questions. Below are the pitfalls students miss most often.
- Mixing Verb Forms: A frequent mistake is combining different verb forms within the same list or pair. One item may use a gerund while another uses an infinitive, breaking parallel structure. Always check that verbs follow the same pattern.
- Uneven Lists: In parallel lists, students often focus on the first two items and miss a third that changes form. The SAT commonly hides this error at the end of a series. Each item must match grammatically for correct parallelism.
- Mismatched Paired Constructions: Paired phrases like both…and or not only…but also must connect ideas with the same structure. The test often makes one side a phrase and the other a clause. Compare both sides carefully to confirm balance.
- Faulty Comparisons: SAT parallelism questions frequently include comparisons that mix unlike structures. A noun might be compared to a clause or an action to a thing. Make sure both sides of the comparison are logically and grammatically similar.
- Distracting Extra Words: Modifiers and descriptive phrases can hide parallelism errors. The SAT adds extra detail to pull attention away from structure. Ignore unnecessary words and focus on the core elements being compared or listed.
The best way to avoid these parallelism SAT traps is through targeted practice. A focused SAT QBank lets you drill parallel structure questions and review explanations that show exactly where structure breaks down.
Best Strategies for Parallel Structure SAT Writing Questions
Parallel structure errors are easier to catch when you focus on grammar patterns rather than overall meaning. SAT parallel structure questions reward a systematic approach and careful comparison of sentence parts. Using the strategies below will help you improve accuracy when applying parallelism for SAT success.
- Identify the Pattern First: Before evaluating answer choices, determine the grammatical form being used. Check whether the sentence is built around nouns, verbs, or phrases. Once you recognize the pattern, you can quickly eliminate options that break parallel structure.
- Line Up the Elements: Mentally align the items in a list, pair, or comparison. Read each element one by one and see if they match in form. This technique makes small differences in structure much easier to spot.
- Watch for Signal Words: Words like and, or, but, both…and, and not only…but also often introduce parallel ideas. When you see these signals, expect parallel structure on both sides. SAT parallel structure questions frequently place errors near these connectors.
- Simplify the Sentence: Remove extra descriptive phrases to reveal the core structure. Stripping the sentence down helps you focus on the parts that must be parallel. This strategy is especially useful for longer SAT writing questions.
- Trust Grammar Over Sound: Some incorrect sentences may sound acceptable but still violate parallelism rules. Always rely on grammatical consistency rather than what sounds right. Clear structure is the standard the SAT uses to judge correctness.
If you prefer structured review and examples you can revisit anytime, an SAT prep book can reinforce parallelism rules with clear explanations and practice sets designed around real test patterns.
Practice with SAT Parallelism Questions
Practicing SAT parallelism questions helps you spot structural errors quickly and choose clearer, more balanced sentence options. With regular practice, you’ll learn to recognize mismatched lists, phrases, and comparisons and fix them with confidence.
Passage: Insufficient Sleep Among Teenagers
Insufficient sleep is common among high school students and has been associated with an increased risk for motor vehicle crashes, sports injuries, and [Q#1] also an increased risk of occupational hazards. US high school students who get fewer than 7 hours of sleep are also more prone to risky behavior, be it texting while driving, [Q#2] when they infrequently use a seat belt, or drinking and driving.
Insufficient sleep directly contributes to injury risk, slowing reaction time, [Q#3] impair the ability to pay attention, or causing a driver to fall asleep. Thus, not getting enough sleep might cause adolescent drivers to take more risks and [Q#4] have disregarded the possibility of negative consequences.
Teens may have unavoidable reasons for insufficient sleep; some lose rest by working at night, [Q#5] to study late, or participating in extracurricular activities like theater or band. Historically, however, students have viewed the evening as the only time to pursue their own interests, playing video games late into the night or [Q#6] socializing with friends on their phones or computers.
Even more problematic for sleep, students' circadian rhythms, or internal biological clocks, often cause wakefulness at night, [Q#7] they increase sleepiness during the day, and contribute to tiredness during school. In addition, depression has been identified as another problem among teens, often accompanied by "at risk" behaviors or sleepiness that could cause them to crash their car, not to mention [Q#8] injured themselves or others.
To ensure adequate sleep, adolescents can practice good sleep hygiene. These habits include a consistent schedule with the same bedtime and wake-up time each day, a technology-free bedroom with no computers or cell phones, and [Q#9] a dark room with minimal exposure to light. To help their teens get enough sleep, parents should establish reasonable bedtimes, [Q#10] limit when (only before a set time or "media curfew") and where (not in their bedrooms) their teenagers can use electronic devices, and ensure the house is quiet and conducive to rest.
Unfortunately, early school start times can also contribute to a lack of sleep among adolescents. Delaying school start times has been proposed as a means of ensuring that adolescents are livelier, can think better, [Q#11] and they are more awake, are ready to learn. Unfortunately, some students wake up feeling tired in spite of adequate sleep, which might be an indication of poor sleep quality or an underlying health condition. Poor sleep quality might result from bad sleeping habits, an inconducive sleep environment (too warm, too noisy, cell phones in the bedroom), or a sleep disorder. Teens should be aware of these potential problems because the recommendation, according to the National Sleep Foundation, is for adolescents aged 14–17 years to sleep 8–10 hours per night and [Q#12] getting good quality rest.
Question
Insufficient sleep is common among high school students and has been associated with an increased risk for motor vehicle crashes, sports injuries, and also an increased risk of occupational hazards.
| A. NO CHANGE | |
| B. for occupational hazards. | |
| C. occupational hazards. | |
| D. it also increases the risk of occupational hazards. |
Explanation
Rule: Items in a series should maintain parallel structure by using the same parts of speech for each item.
If the underlined portion is a list, see which each answer choice matches the grammatical structure of the other listed items.
The first two items for which "insufficient sleep" presents "an increased risk" are given as objects of the preposition "for." Both contain an adjective followed by a noun. The only answer that also uses an adjective followed by a noun is occupational hazards.
(Choice A) "An increased risk" is already used before the preposition "for," so repeating these words would be unnecessary as well as not parallel to the other items after "for."
(Choice B) This answer repeats the preposition "for," which is used before the first item but not before the second. All the items would have to include "for" in order to maintain parallel structure.
(Choice D) "It also increases the risk of occupational hazards" is an independent clause. Because none of the other items are independent clauses, this answer doesn't maintain parallel structure.
Things to remember:
Items in a series should maintain parallel structure by using the same parts of speech.
Passage: Insufficient Sleep Among Teenagers
Insufficient sleep is common among high school students and has been associated with an increased risk for motor vehicle crashes, sports injuries, and [Q#1] also an increased risk of occupational hazards. US high school students who get fewer than 7 hours of sleep are also more prone to risky behavior, be it texting while driving, [Q#2] when they infrequently use a seat belt, or drinking and driving.
Insufficient sleep directly contributes to injury risk, slowing reaction time, [Q#3] impair the ability to pay attention, or causing a driver to fall asleep. Thus, not getting enough sleep might cause adolescent drivers to take more risks and [Q#4] have disregarded the possibility of negative consequences.
Teens may have unavoidable reasons for insufficient sleep; some lose rest by working at night, [Q#5] to study late, or participating in extracurricular activities like theater or band. Historically, however, students have viewed the evening as the only time to pursue their own interests, playing video games late into the night or [Q#6] socializing with friends on their phones or computers.
Even more problematic for sleep, students' circadian rhythms, or internal biological clocks, often cause wakefulness at night, [Q#7] they increase sleepiness during the day, and contribute to tiredness during school. In addition, depression has been identified as another problem among teens, often accompanied by "at risk" behaviors or sleepiness that could cause them to crash their car, not to mention [Q#8] injured themselves or others.
To ensure adequate sleep, adolescents can practice good sleep hygiene. These habits include a consistent schedule with the same bedtime and wake-up time each day, a technology-free bedroom with no computers or cell phones, and [Q#9] a dark room with minimal exposure to light. To help their teens get enough sleep, parents should establish reasonable bedtimes, [Q#10] limit when (only before a set time or "media curfew") and where (not in their bedrooms) their teenagers can use electronic devices, and ensure the house is quiet and conducive to rest.
Unfortunately, early school start times can also contribute to a lack of sleep among adolescents. Delaying school start times has been proposed as a means of ensuring that adolescents are livelier, can think better, [Q#11] and they are more awake, are ready to learn. Unfortunately, some students wake up feeling tired in spite of adequate sleep, which might be an indication of poor sleep quality or an underlying health condition. Poor sleep quality might result from bad sleeping habits, an inconducive sleep environment (too warm, too noisy, cell phones in the bedroom), or a sleep disorder. Teens should be aware of these potential problems because the recommendation, according to the National Sleep Foundation, is for adolescents aged 14–17 years to sleep 8–10 hours per night and [Q#12] getting good quality rest.
Question
Insufficient sleep directly contributes to injury risk, slowing reaction time, impair the ability to pay attention, or causing a driver to fall asleep.
| A. NO CHANGE | |
| B. sleep deficit impairing | |
| C. to impair | |
| D. impairing |
Explanation
Rule: Items in a series should maintain parallel structure by using the same parts of speech for each item.
Determine if the underlined word is part of a list, and if so, make a note of the grammatical pattern so that you can choose the answer that matches that pattern.
Each participle begins a noun phrase that describes "insufficient sleep." Because the first participle "slowing" and the third participle "causing" are both present participles that end in "–ing," the second one should also end in "–ing." Therefore, the correct answer is impairing.
(Choices A, B, and C) None of these answers match the grammatical pattern of the other items in the list, so they don't maintain parallel structure.
- Choice A: "Impair" is a present tense verb instead of a present participle "–ing" verb.
- Choice B: The two other items in the series place a participle before a noun phrase, but this answer puts the noun phrase "sleep deficit" first, so this order isn't the same as the other listed items.
- Choice C: "To impair" is an infinitive, not a participle.
Things to remember:
To maintain parallel structure, series items often use the same parts of speech (ex. present participles) in the same order. (Ex. He plans on going home, taking a shower, and watching TV.)
Passage: Insufficient Sleep Among Teenagers
Insufficient sleep is common among high school students and has been associated with an increased risk for motor vehicle crashes, sports injuries, and [Q#1] also an increased risk of occupational hazards. US high school students who get fewer than 7 hours of sleep are also more prone to risky behavior, be it texting while driving, [Q#2] when they infrequently use a seat belt, or drinking and driving.
Insufficient sleep directly contributes to injury risk, slowing reaction time, [Q#3] impair the ability to pay attention, or causing a driver to fall asleep. Thus, not getting enough sleep might cause adolescent drivers to take more risks and [Q#4] have disregarded the possibility of negative consequences.
Teens may have unavoidable reasons for insufficient sleep; some lose rest by working at night, [Q#5] to study late, or participating in extracurricular activities like theater or band. Historically, however, students have viewed the evening as the only time to pursue their own interests, playing video games late into the night or [Q#6] socializing with friends on their phones or computers.
Even more problematic for sleep, students' circadian rhythms, or internal biological clocks, often cause wakefulness at night, [Q#7] they increase sleepiness during the day, and contribute to tiredness during school. In addition, depression has been identified as another problem among teens, often accompanied by "at risk" behaviors or sleepiness that could cause them to crash their car, not to mention [Q#8] injured themselves or others.
To ensure adequate sleep, adolescents can practice good sleep hygiene. These habits include a consistent schedule with the same bedtime and wake-up time each day, a technology-free bedroom with no computers or cell phones, and [Q#9] a dark room with minimal exposure to light. To help their teens get enough sleep, parents should establish reasonable bedtimes, [Q#10] limit when (only before a set time or "media curfew") and where (not in their bedrooms) their teenagers can use electronic devices, and ensure the house is quiet and conducive to rest.
Unfortunately, early school start times can also contribute to a lack of sleep among adolescents. Delaying school start times has been proposed as a means of ensuring that adolescents are livelier, can think better, [Q#11] and they are more awake, are ready to learn. Unfortunately, some students wake up feeling tired in spite of adequate sleep, which might be an indication of poor sleep quality or an underlying health condition. Poor sleep quality might result from bad sleeping habits, an inconducive sleep environment (too warm, too noisy, cell phones in the bedroom), or a sleep disorder. Teens should be aware of these potential problems because the recommendation, according to the National Sleep Foundation, is for adolescents aged 14–17 years to sleep 8–10 hours per night and [Q#12] getting good quality rest.
Question
In addition, depression has been identified as another problem among teens, often accompanied by "at risk" behaviors or sleepiness that could cause them to crash their car, not to mention injured themselves or others.
| A. NO CHANGE | |
| B. injuring | |
| C. injure | |
| D. have injured |
Explanation
Rule: When a conjunction connects two infinitives, they should both be present tense verbs.
Determine if the underlined verb is connected to another verb in the sentence. If so, make sure those two verbs match.
"Not to mention" connects the infinitive "to crash" with a second verb, which should be in the present tense because it functions as a second infinitive. (Ex. The goal of every student driver should be to maneuver carefully, not to mention [to] keep everyone in the car safe.) Of the choices, the only option that creates parallel structure is injure.
(Choice A) "Injured" is a past tense verb that can't be part of an infinitive and, therefore, doesn't match the first verb. (Incorrect: The coach shouldn't allow the students to play recklessly or [to] injured others.)
(Choice B) "Injuring" can't be preceded by "to," so it can't create a second infinitive that is parallel to the first verb. (Incorrect: The dart thrower wanted to hit the target, not [to] injuring others.)
(Choice D) Although "have injured" could be preceded by "to," it wouldn't be parallel with the infinitive form "crash" from earlier in the sentence. (Not parallel: I need to sleep and have gotten more rest.)
Things to remember:
Two infinitive verbs can be parallel when only the first is preceded by "to" as long as the second is also in the present tense form.
Passage: Insufficient Sleep Among Teenagers
Insufficient sleep is common among high school students and has been associated with an increased risk for motor vehicle crashes, sports injuries, and [Q#1] also an increased risk of occupational hazards. US high school students who get fewer than 7 hours of sleep are also more prone to risky behavior, be it texting while driving, [Q#2] when they infrequently use a seat belt, or drinking and driving.
Insufficient sleep directly contributes to injury risk, slowing reaction time, [Q#3] impair the ability to pay attention, or causing a driver to fall asleep. Thus, not getting enough sleep might cause adolescent drivers to take more risks and [Q#4] have disregarded the possibility of negative consequences.
Teens may have unavoidable reasons for insufficient sleep; some lose rest by working at night, [Q#5] to study late, or participating in extracurricular activities like theater or band. Historically, however, students have viewed the evening as the only time to pursue their own interests, playing video games late into the night or [Q#6] socializing with friends on their phones or computers.
Even more problematic for sleep, students' circadian rhythms, or internal biological clocks, often cause wakefulness at night, [Q#7] they increase sleepiness during the day, and contribute to tiredness during school. In addition, depression has been identified as another problem among teens, often accompanied by "at risk" behaviors or sleepiness that could cause them to crash their car, not to mention [Q#8] injured themselves or others.
To ensure adequate sleep, adolescents can practice good sleep hygiene. These habits include a consistent schedule with the same bedtime and wake-up time each day, a technology-free bedroom with no computers or cell phones, and [Q#9] a dark room with minimal exposure to light. To help their teens get enough sleep, parents should establish reasonable bedtimes, [Q#10] limit when (only before a set time or "media curfew") and where (not in their bedrooms) their teenagers can use electronic devices, and ensure the house is quiet and conducive to rest.
Unfortunately, early school start times can also contribute to a lack of sleep among adolescents. Delaying school start times has been proposed as a means of ensuring that adolescents are livelier, can think better, [Q#11] and they are more awake, are ready to learn. Unfortunately, some students wake up feeling tired in spite of adequate sleep, which might be an indication of poor sleep quality or an underlying health condition. Poor sleep quality might result from bad sleeping habits, an inconducive sleep environment (too warm, too noisy, cell phones in the bedroom), or a sleep disorder. Teens should be aware of these potential problems because the recommendation, according to the National Sleep Foundation, is for adolescents aged 14–17 years to sleep 8–10 hours per night and [Q#12] getting good quality rest.
Question
Delaying school start times has been proposed as a means of ensuring that adolescents are livelier, can think better, and they are more awake, are ready to learn.
| A. NO CHANGE | |
| B. and | |
| C. and therefore | |
| D. and, because they |
Explanation
Rule: When connecting items in a list, "and" is used between the last two items.
Read the entire sentence, noting the punctuation and wording already there to make sure the selected answer is grammatically correct.
The commas after "livelier" and "better" indicate the first two verb phrases that are items in the list of what delayed start times ensure for adolescents. "And" indicates that there is only one more item in the list. That item is "ready to learn." What comes before this last item introduces a reason that adolescents are ready to learn: "because they are more awake."
In this case, a comma would be placed after "awake" to mark a separation between the introductory information and the last item in the list. Therefore, the grammatically correct option is and, because they.
(Choice A) "They are more awake" is another independent clause, but the other items in the list are verb phrases, keeping this choice from being parallel.
(Choices B and C) These answers treat the introductory information as another item in the list. They incorrectly place the "and" between the two middle items in the list rather than the last two items in the list.
Things to remember:
When items in a list are joined by "and," make sure this conjunction occurs between the last two listed items.
Frequently Asked Questions
How often does parallelism appear on the SAT Writing section?
Parallelism appears regularly on the SAT Reading and Writing section, often as part of sentence structure or clarity questions. You can expect to see at least a few SAT parallel structure questions on most tests. These questions are usually embedded in longer passages rather than presented on their own. Because they test logic and consistency, they are considered medium to high value questions.
Which type (lists, phrases, comparisons) is most common?
Parallel lists are the most common form tested on the SAT. Lists are easy to write incorrectly and easy for the test to hide errors in. Parallel phrases connected by conjunctions appear next most often, while comparisons show up slightly less frequently. Practicing all three types is still important for strong parallelism SAT performance.
Is “either/or” or “not only/but also” a special trap?
Yes, these paired constructions are a common trap in SAT parallel structure questions. The SAT often makes one side a phrase and the other a clause. Both sides must match in grammatical form for the sentence to be correct. Always check both halves carefully before choosing an answer.
Can a sentence have more than one parallelism error?
Yes, a sentence can contain multiple parallelism errors, especially in longer or more complex structures. The SAT may include more than one mismatched element within a list or across paired ideas. However, fixing the main structural pattern often corrects the remaining issues. Recognizing the core parallel form helps you avoid confusion.
