When pairing ideas, underscore their connection by expressing them in similar grammatical form. Paired ideas are usually connected in one of these ways:
Parallel ideas linked with coordinating conjunctions
Coordinating conjunctions (and, but, or, nor, for, so, and yet) link ideas of equal importance. When those ideas are closely parallel in content, they should be expressed in parallel grammatical form.
The revision balances the nouns use and capitalization.
The revision balances the verb reducing with the verb extending.
Parallel ideas linked with correlative conjunctions
Correlative conjunctions come in pairs: either…or, neither…nor, not only…but also, both…and, whether…or. Make sure that the grammatical structure following the second half of the pair is the same as that following the first half.
The words a prolific inventor follow not only, so a successful entrepreneur should follow but also. Repeating was creates an unbalanced effect.
To change my flight, which follows either, should be balanced with to take the train, which follows or.
Comparisons linked with than or as
In comparisons linked with than or as, the elements being compared should be expressed in parallel grammatical structure.
To speak is balanced with to ground.
When you are quoting from a source, parallel grammatical structure—such as writing…keeping—helps create continuity between your sentence and the words from the source.