Use Parallel Structure to Guide the Reader

Getting What You Want from Your Science Writing Part X

computer_keyboardParallel construction signals to the reader that two ideas are of equal importance. If two or more ideas or items are connected by a coordinating conjunction such as “and”, “but” or “or”, then those ideas should be expressed in parallel or equivalent grammatical constructs. Items and ideas of equal importance should be presented using equivalent grammatical structures. Items in a list should be parallel: all verbal phrases, all nouns, etc. Parallel construction guides your reader and helps your reader organize concepts on a first read of your text.

Consider this list of writing tips:

  • Know your audience.
  • Read and follow the instructions to authors.
  • Do the math.
  • Use, but do not trust, spell-check programs.
  • Avoid unnecessary passive voice.
  • Use parallel structure.
  • Provide context for new ideas.
  • Proofread and review your work.

Each of the items in this list is a complete sentence written in the imperative voice. The items of the list are parallel. The uniform structure allows the reader to focus on the content of each writing tip.

Parallel structure is important for sentences too, particularly long ones. Consider this sentence:

“Technical writing ranges from editing of online help files, document engineering, user’s manual for software and hardware, to writing of product sheets and other product pertaining instructions.”

This sentence contains four items, presumably all of equal importance, yet two are presented as participles, one as a gerund, and one as noun. The reader has to strain to figure out what the writer is saying.

Here’s one rewrite:

“Technical writing involves editing and writing many kinds of documents including online help files, user’s manuals, product information sheets, and product instructions.”

Or for a simpler example:

“The competitor’s protocol is both a long procedure and very tedious.”


“The competitor’s protocol is long and tedious.”

Parallel structure can guide your reader, providing clues to equivalent ideas by putting them in equivalent grammatical constructions. Using parallel constructs aids in the rhythm and flow of your writing, and will help your writing be more clear on the first read.

The following two tabs change content below.
Michele Arduengo

Michele Arduengo

Supervisor, Digital Marketing Program Group at Promega Corporation
Michele earned her B.A. in biology at Wesleyan College in Macon, GA, and her PhD through the BCDB Program at Emory University in Atlanta, GA where she studied cell differentiation in the model system C. elegans. She taught on the faculty of Morningside University in Sioux City, IA, and continues to mentor science writers and teachers through volunteer activities. Michele manages the digital marketing program team at Promega.

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.