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: John was a good student and top of his class. Sentence2: He dreamed of attending a prestigious university on the east coast. Sentence3: He had worked very hard to be in this position. Sentence4: He received a call from the admission office of the university. Sentence5: He will be attending the campus in the fall.
A:
John, Class, Office