How many times have you heard some variation to the old adage, You can’t add apples and oranges? I dare say, we’ve all heard it repeatedly and may have used the phrase ourselves. It creates a good image and is helpful in understanding a variety of concepts. As it happens, I think it also helps in understanding parallel structure, also called parallel construction or parallelism.
Of course with parallel structure, we’re talking about words and phrases and clauses, not fruit, but the concept is still the same.
The point of parallel structure, like most grammar, is to create clarity and readability:
Parallel structure adds both clout and clarity to your writing. When you use parallel structure, you increase the readability of your writing by creating word patterns readers can follow easily.(“Parallel Structure,” Evergreen Writing Center)
The key, I believe, to utilize parallel construction consistently is the idea of creating word patterns—or putting all the oranges together and all the apples together.
At the word level, parallel structure “adds” nouns with nouns, verbs with verbs, and adverbs with adverbs. Hence, in a list, all the items need to be of like kind:
Catlyn enjoys writing, reading, and sleeping.
Jordan likes books, movies, and to take long walks.
However, these words must also be in the same form. Hence, a verb ending in -ing should not be “added” to a verb in the infinitive form, or the to- form.
Oscar gained a reputation for his blocking, catching, and running.
DeShawn likes hitting blockers, tackling ball carriers, and to strip the ball from the runner.
At the phrase level, parallel structure “adds” phrases of like kind, constructed in a similar way.
Whether at the ball park or at the skate rink, he was always on the go.
Whether at the mall or shopping on line, she’s always looking for a bargain.
Not As Parallel As It Could Be:
Whether by himself or with a group of other guys, he always found something to do.
The last example is not technically lacking in parallelism—the conjunction and “adds” two prepositional phrases. However the first one has no modifiers and the second one has another prepositional phrase modifying it. If the rhythm in the paragraph requires strict parallelism, this last example doesn’t do it.
Here are a few similar example.
Not As Parallel As It Could Be:
He pulled out a box of toys, a pile of comics, and a couple shoes. [The first two nouns are described by prepositional phrases, the last one is not].
Ary prefers driving fast cars, drinking strong drinks, and lounging in front of the TV. [The first two verb forms have objects, the last one is described by a sequence of prepositional phrases].
Parallel structure also applies to compound clauses, that is, to a group of words with a subject and verb.
Dad often spoke of his older sister who put herself through college but who never did anything with her education.
The coach told his players that they should play as a team, that they should share the ball, and not to be selfish.
As with words and phrases, form also matters in the structure of parallel clauses.
The shopper expected that she would find a new dress, that a salesman would ring up her purchase, and that the item would be bagged. [The first two verbs are active, the last is passive].
Apples and oranges. Keep them separate. Your readers will thank you, though they probably won’t know what you’ve done to make your writing so clear and so easy to understand.