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Parallelism (grammar) In grammar, parallelism, also known as parallel structure or parallel construction, is a balance within one or more sentences of similar phrases or clauses that have the same grammatical structure. The application of parallelism improves writing style and readability, and is thought to make sentences easier to process.
Using the same pattern of words to show that two or more ideas have the same level of importance is the definition of parallel structure. Parallel structure is repetition of a certain form, which provides balance and clarity in your writing.