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: Jack was going to go start running. Sentence2: He bought new shoes in order to increase his performance. Sentence3: However, while he was out one day, he turned his ankle. Sentence4: He was not able to run anymore. Sentence5: Jack felt like he wasted his money on new shoes.
A:
Jack