You will be given a definition of a task first, then some input of the task.
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: Eric had a new sled that he couldn't wait to try out. Sentence2: Only there wasn't any snow yet. Sentence3: Finally on Saturday morning he woke up and it had snowed. Sentence4: He called his friend John to meet him on the hill by the school. Sentence5: They took turns riding down the hill on Eric's new sled.
Output:
John, Eric