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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.
Parallel structure is repetition of the same pattern of words or phrases within a sentence or passage to show that two or more ideas have the same level of importance. Parallel structure helps to organize ideas, making a text or speech easier to understand.