Parallelism is one of the most powerful and flexible tools in a writer's arsenal. By using it at the right time and in the right way, you can make your writing unforgettable.
The simplest example of parallelism is to rewrite two clauses in a row with either similar or directly opposing words. Here's an example of a sentence rewritten to include contrasting parallelism:
1) My goal is to help you avoid bad ones and instead draw your attention to the better ones.
2) My goal is to warn you from the bad ones and draw your attention to the good ones.
The second draft reads more smoothly with the word "bad" in the first clause offset by by the word "good" in the second clause. Also, a few minor word substitutions helps create a parallel rhythm in the two clauses: "warn you from the bad ones/draw your attention to the good ones."
You can use parallelism in many forms: You can use it successive clauses, or in successive sentences. You can write sentences with rhythmic parallelism, rhyming parallelism, or both:
This is part of what’s wrong with you -- you do too much singing. Today it’s time to stop singing and start swinging. You can’t sing up on freedom, but you can swing up on some freedom.
--Malcolm X, from "The Ballot or the Bullet" speech
Once you become aware of this technique, you'll start to see examples of it everywhere:
I do not know the dignity of their birth, but I do know the glory of their death.
Douglas MacArthur, from his "Duty, Honor, Country" speech.
If a free society cannot help the many who are poor, it cannot save the few who are rich.
John F. Kennedy, Inaugural Address (the "Ask Not" speech)
But, in a larger sense, we cannot dedicate... we cannot consecrate... we cannot hallow this ground.
Abraham Lincoln, from The Gettysburg Address
Parallelism makes writing and speaking sound poetic, and it makes ordinary words sound extraordinary:
I have a dream that my four little children will one day live in a nation where they will not be judged by the color of their skin but by the content of their character.
--Martin Luther King, Jr., from the "I Have a Dream" speech
Look for opportunities to use parallelism in your writing and add power and emotion to your writing!