Parallelism

In parallel structure, all items in a list or comparison have the same grammatical structure. In other words, you might have a list of nouns, or a list of verbs, but you cannot have a list of mixed nouns and verbs.

According to Writing for Success, “Parallelism creates a sentence of rhythm and balance within a sentence. As readers, we often correct faulty parallelism (a lack of parallel structure) intuitively because an unbalanced sentence sounds awkward and poorly constructed” (para. 2). Sentences are contain parallel structure “sound more aesthetically pleasing because they are balanced. Repetition of grammatical construction also minimizes the amount of work the reader has to do to decode the sentence. Therefore, the reader is able to focus on the main ideas in the sentence instead of how the sentence is put together” (para. 4).

When you create a list or make a comparison, you need to ensure that you are using “parallel structure”.

Ways to Create Parallel Structure^[1]

Creating Parallelism using Coordinating Conjunctions and in Lists

When you connect two clauses using a coordinating conjunction (for, and, nor, but, or, yet, so), make sure that the same grammatical structure is used on each side of the conjunction. Take a look at the following example:

The first sentence uses two different verb forms (to listen, talking). In the second sentence, the grammatical construction on each side of the coordinating conjunction (and) is the same, creating a parallel sentence.

The same technique should be used for joining items or lists in a series:

The first sentence contains two items that use the same verb construction (reduce, cut) and a third item that uses a different verb form (lowering). The second sentence uses the same verb construction in all three items, creating a parallel structure.

Creating Parallelism in Comparative Statements using “Than” or “As”

When you are making a comparison, the two items being compared should have a parallel structure. Comparing two items without using parallel structure can lead to confusion about what is being compared. Comparisons frequently use the words than or as, and the items on each side of these comparison words should be parallel. Take a look at the following example:

In the first sentence, the elements before the comparison word (than) are not equal to the elements after the comparison word. It appears that the writer is comparing an action (swimming) with a noun (a pool). In the second sentence, the writer uses the same grammatical construction to create a parallel structure. This clarifies that an action is being compared with another action.

To correct some instances of faulty parallelism, it may be necessary to add or delete words in a sentence.

In this example, it is necessary to add the verb phrase going for to the sentence in order to clarify that the act of walking is being compared to the act of running.

Creating Parallelism using Correlative Conjunctions

A correlative conjunction is a paired conjunction that connects two equal parts of a sentence and shows the relationship between them. Common correlative conjunctions include the following:

• either…or
• not only…but also
• neither…nor
• whether…or
• rather…than
• both…and

Correlative conjunctions should follow the same grammatical structure to create a parallel sentence. Take a look at the following example:

When using a correlative conjunction, the words, phrases, or clauses following each part should be parallel. In the first sentence, the construction of the second part of the sentence does not match the construction of the first part. In the second sentence, omitting needless words and matching verb constructions create a parallel structure. Sometimes, rearranging a sentence corrects faulty parallelism.

Parallelism in thesis statements

Thesis statements contain a list of topics that you will discuss in your body paragraphs. That list of topics should be in parallel structure.