Parallelism
Combining parts of sentences with and, but, or or requires parallel structure. Parallel, in this sense, means balanced or equal. Items in a list need to be parallel in both grammar and function.
Parallel Grammar
The grammar of listed elements must be parallel. For example, you can join nouns to nouns, adjectives to adjectives, prepositional phrases to prepositional phrases, or clauses to clauses, but you should not join nouns to adjectives, or phrases to clauses if they are a list of similar items.
Parallel
He is tired, lonely, and hungry. (adjectives are joined to adjectives)
She walked to the skytrain, bought a ticket, and got on the westbound train. (verb + noun is joined to verb + noun)
Not Parallel
He is tired, lonely, and hurry. (tired and lonely are adjectives, but hurry is a verb)
She walked to the skytrain, bought a ticket, and she got on the westbound train. (walked to the skytrain and bought a ticket are verb + noun, but she got on the westbound train is a full clause)
Parallel Function
The function of the listed elements must also be parallel. For example, you can join physical description to physical description, but you generally cannot join physical description to feelings.
Parallel
You can get cell phones in red, blue, green, and black. (all are colours)
Maria likes milk, loves tea, and hates coffee. (all describe emotions about food)
They took vegetables, meat, and fruit on the camping trip. (all types of food)
Not Parallel
You can get cell phones in red, blue, shiny, and black. (red, blue, and black are colours, but shiny describes a different aspect of the phone)
Maria likes milk, loves tea, hates coffee, and arrives late. (likes milk, loves tea, and hates coffee are all emotions about food, but arrives late is an action)
They took groceries, drinks, and three green apples on the camping trip. (groceries and drinks are very general food categories that overlap with each other and with the three green apples)
Solving Parallelism Problems
Sometimes it can be hard to put items into a parallel list. For example, if you want to describe a person you know, you may think of adjectives like friendly, kind, and intelligent. However, you may want to say something about the person’s appearance. You may want to say she is tall and has red hair. So, how can these various things be combined so they are more parallel?
Strategy 1: Change parts of speech
Sentence elements can be made parallel by changing the grammatical form or words. For example, to combine two adjectives and a noun into a list, the noun can usually be changed into an adjective form. In the example above, you could change “red hair” into an adjective form “red-headed” like this:
Karen is tall and red-headed.
Strategy 2: Start the parallelism sooner
A second way to solve parallelism problems is to start the parallelism sooner. In our example, you could start the parallelism with the first verb so that the parallel structures are predicate phrases. In this way, you would end up with this sentence:
Karen is tall and has red hair.
Strategy 3: Create multiple parallelisms
This strategy involves making more than one parallel list in a sentence. Let's say you want to combine the following sentences into one.
Karen is quiet.
Karen has red hair.
Karen is funny.
Karen has green eyes.
Karen has a sardonic smile.
In this case, quiet and funny go together because they come after the verb “is” and both are personality qualities. In the same way, red hair, green eyes, and a sardonic smile go together because they come after the verb “has” and all are physical descriptions. So, the combined elements would be like this:
Karen is quiet but funny, and has red hair, green eyes, and a sardonic smile.
Proofreading for Parallelism Problems
You should leave concerns about parallelism until the editing or proofreading stage of writing. These are the steps to follow:
- Go through your paper and identify every time the words and, but, or or are used. Circle them.
- For each circled word, look for the elements in the list. Underline them and mark where the parallelism begins and ends.
- For each list, consider whether all elements are parallel. Consider both grammar and function.
- Change faulty parallelism using the three strategies described earlier: change parts of speech, start the parallelism sooner, or create multiple parallel lists.