Whenever you have a sentence that includes a list, whether that is a list of things, actions or descriptions, that list has to be presented consistently – however the list is structured at the beginning has to be the way the list continues until the end. This organization is called parallel structure. Parallel structure means using the same pattern of words to show that two or more ideas have the same level of importance.
Words and Phrases
With the -ing form (gerund) of words:
Parallel: Mary likes hiking, swimming, and bicycling.
With infinitive phrases:
Parallel: Mary likes to hike, to swim, and to ride a bicycle.
Mary likes to hike, swim, and ride a bicycle.
(Note: You can use “to” before all the verbs in a sentence or only before the first one)
Craig enjoys movies that are exciting, funny, and intellectual
She ate slowly, thoughtfully, and methodically.
With prepositional phrases:
They looked under the sofa, between the cushions, and near the lamp.
In short, however you begin a list like in the sentences above, that structure must remain consistent throughout the list.
Mary likes hiking, to swim, and riding her bicycle.
(notice how the list is inconsistent – it jumps from an -ing form to an infinitive and then back to an -ing form)
Mary likes hiking, swimming, and riding a bicycle.
Mary likes to hike, swim, and bike.
The production manager was asked to write his report quickly, accurately, and in a detailed manner.
(Again, notice the inconsistency – the list following “to write” starts with two adverbs (quickly, accurately), but then ends with a prepositional phrase (in a detailed manner))
The production manager was asked to write his report quickly, accurately, and thoroughly.
The production manager was asked to write his report in a quick, accurate and thorough manner.
The teacher said that he was a poor student because he waited until the last minute to study for the exam, completed his lab problems in a careless manner, and his motivation was low.
(This list jumps from verbs – waited and completed – to nouns – motivation)
The teacher said that he was a poor student because he waited until the last minute to study for the exam, completed his lab problems in a careless manner, and lacked motivation.
A parallel structure that begins with clauses must keep on with clauses. Changing to another pattern or changing the voice of the verb (from active to passive or vice versa) will break the parallelism.
The coach told the players that they should get a lot of sleep, that they should not eat too much, and to do some warm-up exercises before the game.
(This list drifts from clauses (get sleep & not eat too much) into an infinitive verb (to do exercises))
The coach told the players that they should sleep, not eat too much, and do some warm-ups before the game.
Please fix the following sentences which have problems with parallel structure. There will be several ways to correct these sentences.
Michelle likes to drive, fishing and new books.
A bike pump can be used to inflate basketballs, with tires & blowing air at friends.
I had conversations with the Italians, the French, Peruvians and guys from Japan.
She applied to jobs as a waitress, fixing cars, and in the admissions office.
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