Q: In this task, you're given a story (which contains five sentences only). Your task is to find all the characters which are available in the given story.
Sentence1: Sam got in a fight at school. Sentence2: A bully picked on him, and Sam defended himself. Sentence3: But both boys received detention! Sentence4: Sam tried to explain to his parents, but they didn't listen. Sentence5: Sam felt unjustly accused and punished.
A:
Parents, Bully, Sam