When you write, you want readers to understand what you are saying. If you are making lists or comparing items in a sentence, parallel structure must be used, otherwise, you will confuse your reader. This lesson will define and give many examples of parallel sentences.
Train Tracks
When a train from the U.S. passes into Canada, something incredible happens: the tracks in Canada are the same width (gauge) as the train tracks in the U.S. Obviously, this makes sense as Canada is the United States' biggest trading partner. If both countries did not have the same gauge, goods would have to be moved to another train at the border, slowing everything down.
Parallel Structure
Like train tracks being the same gauge makes transporting goods easier, listing or comparing items in a sentence is easier to understand when those items have parallel structure, meaning the words must be formed in the same way or must use the same grammatical structure. This repetition of word form makes the sentence flow correctly and adds clarity for the reader or listener. Let's look at the rules for parallel structure.
Using Parallel Structure with Lists
When making lists, many times you will use one of the seven coordinating conjunctions which join words of equal rank together. They are: for, and, nor, but, or, yet, so (easily remembered by saying FANBOYS).
I like to run, eating, and jump. (not parallel)
The list in this sentence is run, eating and jump. This sentence is not parallel because the grammatical formation of the things you like to do are not the same. We need to make the structure of the words agree with each other.
- I like to run, to eat, and to jump. (parallel) ~OR~
- I like to run, eat, and jump. (parallel) - The first infinitive to works or carries over for all the verbs in the list.
This sentence could also be corrected by making all of the objects in the list into gerunds (a verb that acts as a noun by adding 'ing').
I like running, eating, and jumping. (parallel)
List Mixing Adjectives and Adverbs
In this sentence, we have a list of how the students are expected to do their homework.
All students are expected to do their homework good, quickly and efficient. (not parallel)
Good and efficient are adjectives describing something. Quickly is an adverb talking about the action of doing their homework.
All students are expected to do their homework well, quickly and efficiently. (parallel).
Since this sentence was about how the students were to perform an action, adverbs needed to be used because they modify our action words (verbs).