If two or more ideas are parallel, they are easier to grasp when expressed in parallel grammatical form.  Single words should be balanced with single words, phrases with phrases, clauses with clauses. 

Balance parallel ideas in a series

• Not -- Abused children commonly exhibit one or more of the following symptoms:  withdrawal, rebelliousness, restlessness, and they are depressed.
• But -- Abused children commonly exhibit one or more of the following symptoms:  withdrawal, rebelliousness, restlessness, and depression.  

Balance parallel ideas presented as pairs
Balance parallel ideas linked with coordinating conjunctions (and, but, or, nor, for, so, and yet)

• Not -- At Lincoln High School, vandalism can result in suspension or even being expelled from school.
• But -- At Lincoln High School, vandalism can result in suspension or even expulsion from school.  

Balance parallel ideas linked with correlative conjunctions (either . . or; neither . . . nor: not only . . . but also; both . . . and; whether . . . or)

• Not --Thomas Edison was not only a prolific inventor but also was a successful entrepreneur.
• But -- Thomas Edison was not only a prolific inventor but also a successful entrepreneur.  

Balance comparisons linked with than or as.

• Not -- Mother could not persuade me that giving is as much a joy as to receive.
• But -- Mother could not persuade me that giving is as much a joy as receiving.    

Repeat function words (by, to, that, because, etc.) to clarify parallels.

• Not -- In an attempt to break their bad habit, many smokers try switching to a brand they find distasteful or a low tar and nicotine cigarette.
• But -- In an attempt to break their bad habit, many smokers try switching to a brand they find distasteful or to a low tar and nicotine cigarette.