Saylor.org's English Composition/Parallelism
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In grammar, parallelism is a balance of two or more similar words, phrases, or clauses. The application of parallelism in sentence construction can sometimes improve writing style, clearness, and readability.
"I went to the store, I went to the mall and I went to bed" can be reduced to "I went to the store, to the mall, and to bed" through a parallel construction with "I went"