Parallelism may sound fancy, but on a basic level, it’s just the use of grammatically similar constructions for all items in a series. Sentences that follow the rules of parallelism are typically considered more logical and easier to read. Here is a sentence that lacks parallelism:
- Emus like eating bugs, playing in the sunshine, and to make noises.
This sounds awkward because two of the items in the series (“eating” and “playing”) don’t match the third one (“to make”). The fix is pretty simple – just make them match. The following are all appropriate ways to change this sentence.
- Emus like eating bugs, playing in the sunshine, and making noises.
- The Emus like to eat bugs, to play in the sunshine, and to make noises.
- Emus like to eat bugs, play in the sunshine, and make noises.
If you want to use the infinitive (“to” and then the verb), you can usually choose between including the “to” before every verb and including it only before the first verb.
Now for a harder example. See if you can find the parallelism error here:
- Sweet potatoes are orange, tasty, and can be cooked in a variety of ways.
It’s subtle, but the mistake is that the first and last items (“are orange” and “can be cooked in a variety of ways”) contain verbs (“are” and “can be cooked”), while the second (“orange”) doesn’t.
Again, you just need to make your items match. The following are both acceptable versions of the sentence:
- Sweet potatoes are orange, tasty, and able to be cooked in a variety of ways.
- Sweet potatoes are orange, are tasty, and can be cooked in a variety of ways.
Sometimes it may take some finagling to make sure your writing both follows the rules of parallelism and sounds attractive. If you don’t like either of the above options, for example, you can write around the issue as follows:
- Sweet potatoes are orange and tasty, and they can be cooked in a variety of ways.
Occasionally, in literary writing, authors will deliberately defy the conventions of parallelism. This can work quite well when done for a reason, but in general, following the conventions will make your writing easier to read.