Some issues with parallelism may seem simple enough, but there are still instances where parallel structure can be challenging to understand. Much like the split infinitive controversy, some people will say that the whole idea of parallel structure is still largely a matter of personal writing style. That may or may not be true, and I”ll leave that up to you to decide.
Parallel structure describes when you list three or more items in a sentence. When you do so, it is important these items all “match” with one another. Perhaps the best way to illustrate this is through a series of examples.
Incorrect: I enjoy tennis, basketball, and going for a swim.
Correct: I enjoy tennis, basketball, and swimming.
Here, we have a list of sports (which are nouns). The first sentence is incorrect, because the last item in the list does not match the structure of the preceding two items. This is corrected by switching “going for a swim” with a noun version with the same meaning: swimming.
Incorrect: John was fired because he was late for work, he slacked off while there, and lack of respect.
Correct: John was fired because he was late for work, he slacked off while there, and he disrespected his supervisor.
Each of the items in the list here takes on the form of “he (verb) (more detail),” and the last item in the incorrect example does not follow this form. An alternate way to fix this would be to change the last item to “he had a lack of respect” or something similar.
Whether you’re writing a blog post, an academic essay, or a business proposition, be mindful of how you handle lists. It’s important to maintain parallel structure to the best of your ability, because this can improve clarity and give better “flow” to your writing. Part of this will come from practice, but when in doubt, don’t be afraid to ask for a second opinion for a friend or a colleague.
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