Detailed Instructions: 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.
Q: Sentence1: Hal was a good tennis player but he wasn't the best. Sentence2: He spent a great deal of time reading about his opponents. Sentence3: On the court, he seemed to always come up a bit short. Sentence4: He continued to improve his tennis skill, playing more every day. Sentence5: Unfortunately he never became the best tennis player.
A:
Hal, Opponents