Definition Of Parallel Structure | Smooth Sentence Flow

Parallel structure is one of those grammar skills you spot in writing, even if you can’t name it right away. When a sentence lines up its parts in the same form, your reader glides. When the forms clash, the reader hits a speed bump.

This guide stays practical. You’ll get a clear definition, copy-ready patterns, and ways to fix common slips in essays, emails, résumés, and posts.

Definition Of Parallel Structure In Plain English

Parallel structure means matching the shape of words or phrases that work together. If you start a list with verbs, keep the list as verbs. If you pair two ideas with a connector like “not only … but also,” keep both sides built the same way.

Think of it like stacking identical blocks. The meaning can change from block to block, but the form stays steady. That steadiness helps readers process your message without rereading.

What “Parallel” Means In A Sentence

“Parallel” means side by side and aligned. In writing, alignment shows up in grammar: nouns match nouns, verbs match verbs, clauses match clauses. You’re not repeating the same words. You’re repeating the same pattern.

Parallel structure shows up in lists, paired comparisons, headings, and any spot where you name multiple actions or traits in one breath.

Parallel Structure Definition With Fast Checks

The fastest way to lock parallel structure in place is to choose a pattern, then keep it from start to finish. The table below shows common patterns and a clean repair that keeps the meaning.

Pattern	Not Parallel	Parallel Fix
Three verbs in a list	She likes to hike, swimming, and biking.	She likes to hike, to swim, and to bike.
Three -ing verbs	He spent Saturday cleaning, to shop, and cooking.	He spent Saturday cleaning, shopping, and cooking.
Three nouns	The job needs patience, being careful, and attention.	The job needs patience, care, and attention.
Paired comparison	Her plan is smarter than it is bold.	Her plan is smarter than it is bolder.
Not only … but also	He not only wrote the report but also was presenting it.	He not only wrote the report but also presented it.
Either … or	You can either submit online or by dropping it off.	You can submit either online or in person.
Consistent clauses	I value people who listen, who are honest, and they show up.	I value people who listen, who are honest, and who show up.
Matched headings	Planning Your Trip / Packing List / How You Save Money	Planning Your Trip / Packing Your Bag / Saving Money

Why Parallel Structure Makes Writing Easier To Read

Readers don’t want to decode grammar. They want your point. Parallel structure keeps attention on meaning because the form stays predictable.

It also helps you sound steady. A clean list feels deliberate. A crooked list can feel rushed, even when the ideas are solid.

Where Readers Notice It Fast

• Lists: steps, features, reasons, pros and cons.
• Comparisons: “more X than Y,” “as X as Y.”
• Paired connectors: “not only … but also,” “either … or,” “both … and.”
• Headings: a set of titles that should feel like a matched set.

How To Check A Sentence For Parallel Structure

When something feels off, don’t guess. Run a quick check. It takes a minute and saves you from clunky revisions later. If you want extra patterns to compare against, the UNC Writing Center parallelism page lays out clear before-and-after samples.

Step 1: Mark The List Or Pair

Find the spot where the sentence stacks items: a comma list, items after a colon, or two halves joined by a paired connector. That’s where parallel structure lives.

Step 2: Name The Form

Ask what each item is. Is it a noun, a verb, an “-ing” verb, an adjective, or a full clause? If you can label the first item, you can match the rest.

Step 3: Make The Forms Match

Pick one structure and rewrite the odd item to fit. Change as little as you can so your meaning stays intact.

Step 4: Read It Out Loud

This is the gut check. If your voice stumbles, your reader will too. A parallel list often sounds smoother on the first read.

Common Parallel Structure Errors And Clean Fixes

Most parallel structure problems come from mixing forms mid-list. You start with one pattern, then drift. These slips show up a lot in student writing and everyday work writing.

Mixing “To” Verbs And “-ing” Verbs

Not parallel: The goal is to reduce costs, improving quality, and to speed delivery.

Parallel fix: The goal is to reduce costs, to improve quality, and to speed delivery.

If you like “-ing” lists better, flip the whole list: reducing costs, improving quality, and speeding delivery. Consistency wins either way.

Switching From Nouns To Clauses

Not parallel: The workshop covers planning, drafting, and how you revise.

Parallel fix: The workshop covers planning, drafting, and revising.

Uneven Comparisons

Not parallel: This class is more helpful than last semester.

Parallel fix: This class is more helpful than last semester’s class.

Comparisons need comparable items. Match the thing to the thing: class to class, plan to plan, habit to habit.

Correlative Conjunction Traps

Paired connectors set a strict pattern. Once you start one side, the other side must echo it.

• Both … and: She is both smart and hardworking.
• Either … or: You can either call or email.
• Not only … but also: He not only studied but also took notes.

If a sentence feels tangled, rewrite it with two clean verbs or two clean nouns. You’ll feel the difference.

Parallel Structure In Essays, Reports, And Resumes

Academic writing leans on lists: thesis points, argument reasons, evidence types, and steps in a method section. Parallel structure keeps those lists clear so your reader can track your logic.

In résumés, parallel verbs are a must. Bullets that begin with action verbs scan well. If one bullet starts with a verb, don’t let the next one start with a noun phrase.

Strong Thesis Lists

When you write a thesis with three points, keep all three points in the same form.

Not parallel: This paper argues that remote work saves time, boosts morale, and employees can focus better.

Parallel fix: This paper argues that remote work saves time, boosts morale, and improves focus.

Clean Resume Bullets

Pick past-tense verbs for past roles and present-tense verbs for current roles. Then keep each bullet in that same tense.

Not parallel: Managed a team of five, improving onboarding, and training new hires.

Parallel fix: Managed a team of five, improved onboarding, and trained new hires.

Parallel Structure In Headings, Bullets, And Study Notes

If you’ve ever written headings like “Planning,” “Drafting,” and “How I Edited,” you’ve seen why parallel structure matters past sentence level. When headings match, the page feels orderly and skimmable. When they don’t, the reader pauses and wonders why one line sounds like a title and the next sounds like a question.

Try this quick move: start each heading with the same part of speech. If you use verbs, use verbs for the whole set. If you use noun phrases, keep them all as noun phrases. The same idea works in study notes and slide decks, where each bullet should start in the same style.

One more tip: keep verb tense steady in a bullet list. Mixing “Completed,” “Completing,” and “Complete” in the same list can make your work sound scattered, even when it isn’t.

Two Reliable Ways To Fix Parallel Structure When You’re Stuck

Sometimes a sentence is so messy you can’t spot the pattern. These two moves work when your first edit still sounds off.

Rewrite The List After A Colon

Colons are great for lists because they separate setup from items. If a list keeps breaking, rewrite it after a colon and choose one form.

Draft: To finish the project, we need research, writing the draft, and to edit.

Fix: To finish the project, we need to research, to draft, and to edit.

Turn Each Item Into A Full Sentence First

This trick works well when you’re juggling long items. Write each item as its own sentence, then align them.

• I need to call the client.
• I need to send the invoice.
• I need to schedule the follow-up.

Now compress them: I need to call the client, send the invoice, and schedule the follow-up.

Parallel Structure During Editing

Here’s where the definition of parallel structure turns into a repeatable editing habit. Scan for lists and paired connectors during your last pass. Fixing these spots often lifts clarity more than swapping adjectives or trimming a few words.

Purdue OWL explains the core patterns and shows more repairs on its parallel structure page, which is handy when you want extra sentence models.

Parallel Structure Checklist For Final Pass

Use this checklist right before you hit submit. It’s short on purpose, and it works well for essays and posts.

Spot To Scan	What To Match	Quick Fix
Comma lists	Nouns with nouns, verbs with verbs	Rewrite the odd item to match the first
Bulleted lists	Verb tense and opening form	Start each bullet with the same verb style
After a colon	All items in one pattern	Choose “to + verb” or “-ing” and keep it
Both … and	Two adjectives, two nouns, or two verbs	Swap one side into the other’s form
Either … or	Same grammar on both choices	Move the shared words before the pair
Not only … but also	Same tense and structure	Use two matching verbs
Comparisons	Like with like	Name the missing word (“class,” “price,” “plan”)
Headings	Same part of speech	Make each heading start with the same form

Practice Drill That Builds The Habit

Practice makes parallel structure feel automatic. Here’s a short drill you can run in ten minutes.

Write Three Lists In Three Styles

1. Write a “to + verb” list: to research, to draft, to revise.
2. Write an “-ing” list: researching, drafting, revising.
3. Write a noun list: research, draft, revision.

Then take one idea and rewrite it in all three styles. You’ll start noticing the pattern choices you like most.

Fix One Paragraph From Your Own Draft

Pick a paragraph with a list or two. Mark every paired word like “both” or “either.” Then make the paired parts match. You’ll often trim words while you fix the structure, which is a nice bonus.

One Clean Rule To Keep On Your Desk

If you can’t decide which form to use, copy the first item’s grammar and match the rest. That single habit keeps lists tidy, comparisons fair, and headings consistent.