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.

Example Input: Sentence1: Will was moved up a grade because he was so smart. Sentence2: The teachers warned his dad that he wouldn't grow emotionally. Sentence3: His dad insisted on moving him up a grade. Sentence4: Will was hated throughout school. Sentence5: He is now a very confused and disliked adult.
Example Output: Will, Dad, School, Teachers

Example Input: Sentence1: My sister is afraid of spiders. Sentence2: She jumps and screams every time she sees one. Sentence3: I love teasing her with spiders and watching her run away. Sentence4: At school, my sister learned about spiders and was no longer afraid. Sentence5: Now I can't have fun teasing her about spiders.
Example Output: I (myself), My sister, Spider, Spiders

Example Input: Sentence1: Chris wanted to take up a new hobby. Sentence2: He knew he wanted something relaxing. Sentence3: He asked his friends for advice. Sentence4: His friends suggested fishing. Sentence5: Chris began fishing and enjoyed it.
Example Output:
Chris, Friends