Faulty Parallelism (FP)

There are many forms of parallelism. In complex sentences with multiple clauses, it is often the case that several nouns or clauses are governed by one verb, or that one subject is followed by multiple verbs. Where clauses do function co-ordinately in this way, make sure they have equivalent prepositions, verb tenses, and parts of speech.

Faulty parallelism is a frequent problem in undergraduate essays. Generally, I will simply rewrite your sentence rather than explain why the parallelism is faulty. Try to figure out why your sentence is not parallel and why my version of your sentence is parallel.

The examples below are from real student papers (slightly modified to disguise their origin):

Wrong: Francis Meres praised Shakespeare for comedy and writing tragedies.
Right: Francis Meres praised Shakespeare for comedy and tragedy.
Right: Francis Meres praised Shakespeare for writing comedies and tragedies.

Wrong: The names of these establishments allow us to interpret the landscape, the transportation and communication systems in effect, and to create a toponymic geography of the route.
Solution 1: The names of these establishments allow us to interpret the landscape, to identify the transportation and communication systems in effect, and to create a toponymic geography of the route.
Solution 2: The names of these establishments allow us to interpret the landscape, identify the transportation and communication systems in effect, and create a toponymic geography of the route.
Solution 3:The names of these establishments allow us to interpret the landscape and the prevailing transportation and communication systems, and to create a toponymic geography of the route.