Detecting the tone of a story is similar to picking up on tone of voice. It's not what
is being said or done — it's a matter of how
. According to the Literary Terms & Poetry Glossary, tone
is "the manner in which an author expresses his or her attitude; the intonation of the voice that expresses meaning. Tone is described by adjectives, and the possibilities are nearly endless. Often a single adjective will not be enough, and tone may change from chapter to chapter or even line to line. Tone is the result of allusion, diction, figurative language, imagery, irony, symbol, syntax, style, and so on."
Sounds overwhelming? One trick that may help you figure out the tone of the story that you're reading is to imagine a key scene from the story as a movie. What sort of music would be playing in the background? Do you imagine something dark and moody, light and peppy, somber and thoughtful? Music is a tool often used in movies to emphasize tone.
As the definition above indicates, writers use words to set the tone. Take a look at the descriptions in your story. A story with a dark, ominous tone will probably have more negative descriptions than a light, happy comedy. A story with a suspenseful, adventurous tone will probably have lots of short sentences and brief, matter-of-fact descriptions. A sad, romantic story will often have long, detailed, sentimental descriptions. Try to visualize the scene and hear the characters voices as you read, and you'll be able to pick out the tone in no time. (Cue the triumphant music!)