Parallelism, also called parallel structure, isn’t something most readers consciously notice. However, un-parallel structure might make reading difficult, even if readers can’t pinpoint what’s wrong. Our job as writers is to make reading as easy as possible. Parallel structure gives readers a road map of how the rest of the article will sound. This helps them get “in the zone” for reading our content. But what is it?
Parallelism is using the same grammatical forms in a sentence.
At its simplest, parallelism can be exemplified by this sentence, paraphrased from the comic: “She likes playing tennis, watching movies, and riding her bike.” Each verb in this sentence is written in the same form.
The more complex issues with parallel structure happen in headings and more complicated lists. One of the easiest ways to explain parallel structure is to use examples, so buckle up. Ready?
Check out this road trip checklist that does not use parallel structure:
- Check Battery.
- Rotate and fill the tires,
- Replacing the Air Filter
- Check Fluid Levels, and
- Get an oil change
Here are just a few of the problems in this (over-exaggerated) bad example: inconsistent capitalization, mismatched word usage, and improper punctuation. Without parallel structure, this list is like driving a lemon during rush hour — clunky and slow-moving. But have no fear! Using this idea of a road trip checklist, we’re going to explore three types of parallel structure that will have readers zipping through our content: titles and headings, bulleted and numbered lists, and in-line lists.
Titles and Headings
First, let’s write a title and the section headings for an article about what readers should do before embarking on a road trip.
5 Things to Do before a Road Trip
Based on the way the title is written, readers will infer that each heading will tell them what to do. Also, since the title specifically mentions the number of things, numbering the headings will make the parallel structure even more cohesive.
1. Check Battery
2. Rotate and Fill Tires
3. Replace Air Filter
4. Check Fluid Levels
5. Change Oil
In these headings, none of the nouns have a preceding article. If only some of them did, like the list in the introduction, that would signal a lack of parallel structure. However, if all the nouns had articles, the structure would be parallel.
At the end of the day, parallel structure is that simple: each heading is written the same way as the others. This lets the readers breeze through headings without having to slow down to figure out what we mean.
Tip: for headings, parallelism also includes things like punctuation and capitalization.
Bulleted and Numbered Lists
Now, let’s say we are writing an article for college students who just bought their first car, and using a pre-trip checklist is just one section of that article. In this case, the checklist would be mentioned in the heading, and the list would be introduced by, you guessed it, an introductory phrase.
If the introductory phrase is closed, it ends in a colon, which makes the list fairly simple.
Follow a Pre-trip Checklist
Having your own car means freedom. But before you speed off to Florida for Spring Break (road trip!), make sure to do the following things to ensure a safe journey:
· check battery
· rotate and fill tires
· clean or replace air filters
· check and top off fluid levels
· change oil
In this case, since the introductory phrase ends with a colon, the list follows the same rules headings would, except that nothing needs to be capitalized or punctuated. If the introductory phrase had said “make sure to do the following five things,” the list would have been numbered.
On the other hand, if the introductory phrase is open-ended and doesn’t use a colon, the bulleted list becomes a bit more complicated.
Follow a Pre-trip Checklist
Having your own car means freedom. But before you speed off to Florida for Spring Break (road trip!), make sure you
· check the car battery
· rotate and fill the tires
· clean or replace the air filter
· check and top off all fluid levels
· change the oil
Since the introductory phrase is open-ended, each bullet point must form a complete, correct sentence when joined with the introductory phrase: “But before you speed off to Florida for Spring Break (road trip!), make sure you check the car battery.” Also, an open-ended list should use bullet points instead of numbers.
As long as the list points are parallel to the introductory phrase and to each other, readers will keep moving right on through our articles without getting stuck in a structural traffic jam.
Tip: you are welcome to use end punctuation in an open-ended list if you want, but it isn’t required.
The rules of parallel headings and bulleted lists also pave the way for parallel in-line lists. Basically, in-line lists use the same rules as open-ended bulleted lists and, of course, require proper punctuation.
Having your own car means freedom. But before you speed off to Florida for Spring Break (road trip!), make sure you check the car battery, rotate and fill the tires, clean or replace the air filter, check and top off all fluid levels, and change the oil.
Even though “get an oil change” is a more common phrase, it isn’t parallel with the other items in the list, which is why we’ve used “change the oil” instead. With in-line lists, all verbs should use the same tense and form (remember the comic?). Here is an example of another, still parallel, way of writing the same list.
Having your own car means freedom. But before you speed off to Florida for Spring Break (road trip!), make sure you get the car battery checked, the tires rotated and filled, the air filter cleaned or replaced, all fluid levels checked and topped off, and the oil changed.
Since the verb “get” applies to all the things in this list, we only need to use it once at the beginning. Just like with open-ended lists, each item in the list should form a complete sentence when joined with the introductory phrase.
Tip: The verb form you choose is up to you and can change with the style and tone of your article – but, as always, consistency is key.
Because the difference between parallel and un-parallel structure can be as small as one word, it’s easy to see why parallelism (or the lack thereof) sometimes goes unnoticed. And while readers may never be able to name what makes great articles so easy to read, writers know that using parallel structure helps everything run more smoothly.