Sentences with parallel structure repeat parts of speech in the same form to create patterns. Parallel sentences organize information efficiently: they minimize structural differences and simplify connections between ideas. If these patterns are predictable, readers are able to focus their attention on the important information in a sentence. These advantages are especially clear in the cases of a parallel lists and correlatives. This resource introduces examples of each, as well as strategies for writing in parallel structure.
A parallel list repeats parts of speech in identical form to communicate a series of ideas. For example, the sentence “I write novels, poems, and plays” uses parallel structure to list what the writer does. Often the list includes a series of verbs and direct objects, as in: “I read books, write novels, and play songs”. Sometimes, a parallel series will list the adjectives that describe the subject of the sentence, such as: “I am excited, energized, and prepared”. Sentences that list actions or things using different parts of speech and word forms are not parallel.
✘ The library is large, it has many people, and there is beautiful architecture and artwork.
✔ The library is large, busy, and beautiful.
✔ The library has plenty of space, people, and beauty.
The last two examples are in parallel structure, using a list of either repeating adjectives or nouns to describe the library, while the first example combines both parts of speech for a more complex sentence pattern. Since the first sentence does not repeat the same part of speech when listing the characteristics of the library, it does not organize the information in an efficient list. The parallel lists are simple and direct in comparison.
Correlatives are sentences that contain two clauses joined by the conjunctions “not only…but also”, “both … and”, “either….or”, “neither…nor”, “whether…or”, and “if….then”. The two clauses often mirror each other, using a predictable pattern to emphasize similarities or contrasts between ideas. For example, the sentence “Not only do I write books, but I also write plays”, uses parallel structure to compare two kinds of activities. Sentences that compare actions or things using different parts of speech and word forms are not parallel.
✘ Her writing is both clear and she writes with simplicity.
✔ Her writing is both clear and simple.
✔ She writes with both clarity and simplicity.
Once again, the last two examples are in parallel structure, using either adjective or noun form to communicate a description, while the first sentence combines both parts of speech to describe the writing. Since additional parts of speech can distract from a contrast or comparison in the sentence, correlatives generally use a consistent, predictable pattern of words in parallel structure to emphasize ideas.
A good strategy for expressing ideas in parallel structure is to look for coordinating conjunctions (words like “and”, “or”, “but” or “so”) and then work through each part of the sentence on its own. Consider:
How would each of these characteristics work in a corresponding sentence, on their own? Here are some individual solutions:
Once these parts resemble each other as individual sentences, they can also combine to form a list:
Of course, since sentences are often more complex than the above examples, it is not always easy to break them into smaller sentences, and then build these up again once these smaller sentences are sufficiently alike. A shorter version of the solution above is simply to decide what part of speech you will use in a sentence like a list or a comparison, and then repeat the part of speech in each part of the sentence, as in the examples above.