Parallel structure

In practice

Parallel structure means giving matching ideas the same grammatical form. Items in a list, the two halves of a comparison and the parts joined by "and", "or" or "not only… but also" should all be built the same way: all nouns, all "-ing" words, all "to" verbs or all full clauses. "She likes hiking, swimming and biking" is parallel; "She likes hiking, swimming and to ride a bike" is not.

It is called parallelism, too, and it is both a grammar rule and a style device. As grammar, it keeps a sentence from stumbling: the reader expects the third item to match the first two, and a mismatch reads as an error. As style, it gives a sentence rhythm and weight, which is why so many famous lines are parallel.

Julius Caesar's "I came, I saw, I conquered" is three clauses of the same shape. Lincoln's "government of the people, by the people, for the people" repeats one pattern with a new preposition each time. The repetition lets the reader feel the list as one idea, and the one word that changes carries the emphasis.

Parallel structure in a speech that finally lands

The banner mixes a clause, an "-ing" phrase and a prepositional phrase, so nobody can chant it: the rhythm breaks on each item. Coach Diaz rebuilds it as three verb-plus-word commands. Nothing new was added, but the matching form makes it easy to say, remember and believe, which is what parallel structure does in an essay, too.

Parallel structure examples, correct and faulty

Lists. Faulty: "The job requires typing, filing and to answer phones." Parallel: "The job requires typing, filing and answering phones." Faulty: "He was tired, hungry and he wanted to go home." Parallel: "He was tired, hungry and ready to go home."

Pairs joined by correlative conjunctions (either… or, neither… nor, both… and, not only… but also). Faulty: "She not only writes novels but also is directing a film." Parallel: "She not only writes novels but also directs films." The words after each half of the pair should match.

Comparisons. Faulty: "Taking the train is cheaper than to drive." Parallel: "Taking the train is cheaper than driving." Faulty: "The climate in Seattle is wetter than Phoenix." Parallel: "The climate in Seattle is wetter than the climate in Phoenix" or "…than Phoenix's."

How to find and fix faulty parallelism

Find the joint. Look for "and", "or", "but", "than", "as" and the correlative pairs, and for any list of three or more. Then stack the items on separate lines, one under another. Mismatches jump out when you can see the items lined up, the way the banner's three phrases do.

Pick one form and convert the rest. Choose the form that reads most naturally, usually the first item's, and rewrite the others to match. Sometimes the cleanest fix is to cut repeated words ("to swim, to run and to bike" becomes "to swim, run and bike"); sometimes it is to repeat them, so the reader can tell where each item starts.

Read the sentence aloud. Faulty parallelism is often easier to hear than to see. If your voice stumbles on the last item, or the sentence sounds like it changed its mind halfway, check the joint again.

Parallelism as a rhetorical device

Speakers use parallel structure to make an idea memorable. John F. Kennedy's "Ask not what your country can do for you; ask what you can do for your country" pairs two parallel clauses and reverses their words, a move called chiasmus. Martin Luther King Jr.'s repeated "I have a dream that…" is parallelism at the scale of a whole passage, known as anaphora when the repetition comes at the start.

Parallel lines also build contrast. Antithesis puts opposing ideas in matching form ("It was the best of times, it was the worst of times"), so the shared shape makes the difference stand out. In an essay, a parallel pair of sentences is a strong way to set up a counterargument and your answer to it.

Groups of three are the most common. Three parallel items feel complete in a way two do not and four rarely improve on. If you are revising a conclusion, a speech or a pitch, look for the place where three matching phrases can carry the idea you most want remembered.

Parallel structure in dialogue and action lines

Characters who speak in parallel sound rehearsed, which is useful when they are. A lawyer's closing argument, a coach's speech, a cult leader's sermon or a politician's slogan earns its rhythm from matching phrases. Characters in ordinary conversation rarely do it, so a sudden parallel line in casual dialogue can signal that someone has been thinking about what to say.

In action lines, parallel structure keeps a sequence quick and readable. "She grabs the keys, kills the lights and slips out the back" reads as one fast beat. Breaking the pattern on purpose, "She grabs the keys, kills the lights. Stops. Someone is already in the car.", is how a writer makes the reader feel the interruption.