Q. What are the rules surrounding the use of fiction and nonfiction and fictional and nonfictional? I know the former are nouns and the latter adjectives, but can you say “a fiction passage”? I suspect not—though I hear it all the time.
A. Yes, you can say “a fiction passage.” A “fictional passage” is something different—a passage that isn’t real. A fiction passage is like a paint sample or a love letter; they all involve nouns used attributively (unlike painted samples or loved letters).