How and Why to Make your Lists Parallel (And what does parallel mean?)

In an earlier post, I looked at how to punctuate bulleted lists.  And I promised to address another important rule for bulleted lists: Write parallel lists. What exactly does that mean?

Writing parallel lists simply means that each item in the list has the same structure. To be parallel, each item in the list might

• start with the same part of speech (e.g., noun, verb)
• use the same verb tense (e.g., present, past, future)
• use the same voice (e.g., active or passive)
• use the same sentence type (e.g., statement, question)

For example, in the bulleted list above, each item starts with a verb in the present tense and includes an example in parenthesis. 

So, why does this matter? Similarly structured information—parallelism in bulleted lists—is easier for the reader to process. The reader’s eye (and ear) is primed for the pattern of the information.

It’s easy to see how parallelism helps the reader by looking at—or reading aloud—a list that is not parallel.

Key elements of a successful staff flu vaccination campaign include

• informing employees about the vaccination plan
• educating employees about its importance
• employees should be notified about when they can get flu shots

Huh? Did you have to read this list twice?  Because the first two bullets begin with a verb form ending in ing (a gerund), beginning the third bullet with a noun (employees) is particularly jarring. It violates the structure set up in the first two bullets.

Here’s the list with the third bullet rewritten using the same structure as the first two.

Key elements of a successful staff flu vaccination campaign include

• informing employees about the vaccination plan
• educating employees about its importance
• notifying employees about when they can get flu shots

Better? Parallel bullets set up a rhythm that the reader can rely on.

Parallelism isn’t a new concept. Julius Caesar knew its power:

• I came.
• I saw.
• I conquered.

Simple to read and understand!

Have you had enough about bulleted lists?  Or do you still have a question that you'd like me to  answer in a blog post?

--Marilynne Rudick

Comments

[dbkayanda]

It's a little known fact that Roman oratory and writing was full of highly parallel lists of concepts. Points like

Veni
Vidi
Vici

were actually called "weighted darts," or "plumbata" in Latin. (Unfortunately for Caesar, bullets had not yet been invented.)