Grammatical parallelism is also called parallel structure, parallel construction, and parallel form. It is the use of equivalent syntax to array equivalent ideas. One place we occasionally violate parallelism is in a series of direct objects.
“Chinua Achebe’s Things Fall Apart is a triumph of literature that everyone in the world should read. However, it may trigger readers who have experienced racism, colonialism, religious persecution, violence, suicide, and more.” (Source)
The terms racism, colonialism, religious persecution, and violence all denote actions that (1) happen to a person and (2) are not necessarily fatal. The term suicide is non-parallel to those terms because it denotes an action that (1) a person does to himself and (2) is necessarily (by definition) fatal.
So, in the author’s unintentional non-parallelism, the reader senses an unintentional, macabre joke: the suicide, being dead, can neither read Mr. Achebe’s book nor suffer any emotional distress triggered by triggers in the book.
The Takeaway: When you write a series of direct objects, check to make sure they are all parallel. Correcting faulty parallelism is one of the quickest fixes you can make during a copy-edit. Parallelism helps make your copy easier to read. Your readers will notice and appreciate it.