Parallel structure, also called parallelism, means using a consistent grammatical pattern for items that do the same job in a sentence. Compare Please sign the form, attach your receipt, and emailing the file with Please sign the form, attach your receipt, and email the file. In the revision, each action fits after please. You can check most lists this way by reading each item with the words it shares.
How to spot faulty parallelism
| Look for | Ask | Try |
|---|---|---|
| Items joined by and or or | Does each item fit after the same opening words? | Read the items one at a time with the shared opening. |
| Pairs such as either … or | What starts immediately after each half of the pair? | Move the first conjunction next to the first item it introduces. |
| Comparisons with than or as | Exactly which two things or actions am I comparing? | Repeat the word that makes the relationship clear. |
Make each list item fit the same opening
Start with the words that introduce the list. In The grant will pay for new shelves, reading lamps, and to replace the carpet, the first two items fit after pay for. For the third, write carpet replacement. If you want to emphasize what the grant will let the library do, recast the whole list as actions. The grant will let us install new shelves, add reading lamps, and replace the carpet.
- Actions in the -ing form. Ravi enjoys collecting maps, planning routes, and exploring unfamiliar neighborhoods. Each item completes Ravi enjoys …
- Infinitives. We plan to photograph the damage, label the images, and file the report. The first to can apply to all three verbs, or you can write to photograph, to label, and to file.
- Clauses. The note says that the south gate is closed, that the west gate is open, and that the shuttle stops there. Repeating that helps the reader see where each reported fact begins.
Use the same test on bulleted lists. Under Before the appointment, please, start each bullet with a verb such as bring, complete, or check. Under Documents to bring, name the documents in each bullet. See Purdue OWL’s guide to parallel structure.
Place paired conjunctions before matching units
Paired conjunctions such as both … and, either … or, neither … nor, and not only … but also show how two items relate. Put each half of the pair directly before the words it introduces.
Draft. You can either pick up your badge at the front desk or at the information booth. Either introduces an action and or introduces a location. If the choice is where to pick up the badge, move either so both halves introduce locations.
Revision. You can pick up your badge either at the front desk or at the information booth.
If the choice involves two actions, put the pair before those actions. You can either pick up your badge at the front desk or request a digital pass. The same placement works when both items share a verb. The fee covers not only the workshop but also the printed materials. Read the MLA Style Center’s guide to paired conjunctions.
Name the two things you’re comparing
In The shipping cost for the lamp is higher than the desk, the sentence compares a cost with a piece of furniture. Use that for the desk to stand for the shipping cost for the desk, or move the comparison to the actions. It costs more to ship the lamp than to ship the desk.
Short comparisons work when readers can supply the missing words. In The new schedule is clearer than the old one, one plainly means schedule, and the second half can leave the verb implied. When a short comparison has two plausible readings, restore the word that settles it. Nora talks to Sam more often than Lee could mean either of these things.
- Nora talks to Sam more often than to Lee. Compare the two people Nora talks to.
- Nora talks to Sam more often than Lee does. Compare how often Nora and Lee each talk to Sam.
For a comparison with as … as, use the same test. In Checking the totals is as important as saving the receipts, the sentence compares the importance of two tasks. See APA Style’s guidance on logical comparisons.
Use repetition for emphasis and vary the rhythm when it helps
Parallelism can give a passage a rhythm readers recognize. Imagine a speaker recalling three requests. We asked for a safer crossing. We asked for better lighting. We asked for a bus stop with a shelter. The repeated opening gives each request equal weight. The short follow-up, We got a sign, shifts the rhythm and puts emphasis on what the group received.
Matching the grammatical job leaves room to vary the length of each item. In We checked the locks, swept the hall, and called the family waiting outside, the final item takes longer to read. Each action still fits with we. In instructions and checklists, matching the openings also makes it easier to scan for the next step.
A worked edit
Draft. The committee wants to shorten the form, clearer instructions, and make it easier to upload documents. Applicants can either upload proof of address online or at the front desk.
- Start with what the committee wants to do. Read each item after wants to. Shorten and make fit. Change clearer instructions to clarify the instructions.
- Check what the two options actually involve. In this example, applicants upload a file online or hand over a copy at the desk. Use two complete action phrases so readers know what to do in each case.
Revision. The committee wants to shorten the form, clarify the instructions, and make it easier to upload documents. Applicants can either upload proof of address online or bring a copy to the front desk.
Practice fixing parallel structure
Revise each sentence to make the list, pair, or comparison clear. For the last one, see if you can explain why it already works.
- Before you leave, close the windows, turn off the lights, and locking the door.
- The kit includes not only a charging cable but also includes a wall adapter.
- The return policy for sale items is stricter than full-price items.
- Amir spends more time at the library than Ben. Revise this to show that Amir spends more time at the library than he spends with Ben.
- We hope to hear from parents, answer their questions, and revise the schedule.
Show the answers
- Before you leave, close the windows, turn off the lights, and lock the door. All three directions start with the same form of verb.
- The kit includes not only a charging cable but also a wall adapter. Includes applies to both objects.
- The return policy for sale items is stricter than the policy for full-price items. Repeat policy so the sentence compares two policies.
- Amir spends more time at the library than with Ben. Adding with shows how Ben fits into the comparison.
- We hope to hear from parents, answer their questions, and revise the schedule. One to can apply to all three verbs.
