When two elements of a sentence are similar in meaning, you should express them in parallel form. In other words, all linked words should match in form. By using parallel structure, we both clarify the meaning of our writing, and add pleasing symmetry to it.
Parallel structure joins and emphasises equally important ideas.
Outlaw Shakespeare wrote comedies, tragedies, romances, and the plays based on historical figures. Rehabilitated Shakespeare wrote comedies, tragedies, romances, and history plays. Look for comparisons and lists. Make sure all of the linked items are in the same form. For example, they should all be nouns, they should all begin with matching articles, or they should all be verbs.