Parallel writing features repeating patterns that add rhythm, balance, and flow to sentences, paragraphs, and essays. Because of its effect on clarity and coherence, parallelism might be the most important skill a writer — of any stripe — can master. A good understanding of parallelism can help improve grammar, too.
Parallel patterns help writers group ideas with equal importance, and they help readers see connections between those ideas. The simplest patterns are made of words, such as items in a series or consistent use of similar adjectives and adverbs. Phrases, clauses, and even whole sentences can be arranged in repeating, parallel patterns.
Any part of a sentence can be repeated, or paralleled, any number of times. A little parallelism goes a long way. Try not to overdo it!