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: Leanna was the smartest student in her class, nothing was hard. Sentence2: She grew to become a conceited person based on her academical prowess. Sentence3: She loved that many of her friends were jealous of the attention. Sentence4: One day her best friend caught her cheating and told everyone. Sentence5: Her reputation was forever ruined and she wasn't considered smart.
Example Output: Her best friend, Her friends, Leanna, Class

Example Input: Sentence1: When Poppy was growing up, she had a very special doll. Sentence2: She took the doll with her everywhere. Sentence3: As she got older, her mother tried to make her give up the doll. Sentence4: Poppy hid the doll so her mother couldn't find it. Sentence5: But Poppy's dog found the doll and chewed it to pieces.
Example Output: Poppy, Dog, Mother

Example Input: Sentence1: Terry was competing for his town's triathlon. Sentence2: He was fit and ready to win. Sentence3: But the competition was fierce and he almost lost. Sentence4: Only with redoubled effort did he managed to push through. Sentence5: He got the gold medal and was very proud of himself.
Example Output:
Competition, Terry