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.
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Question: Sentence1: Romeo thought he was the fastest kid at school. Sentence2: Romeo challenged his friend to a race on the track. Sentence3: Both of the racers lined up and prepared to take off! Sentence4: However, Romeo's foot slipped and he ended up tripping himself! Sentence5: He skinned his knee badly and was taken away to the nurse.

Answer: Racers, Friend, Romeo

Question: Sentence1: My wife hates her job. Sentence2: She is a teacher to sixth graders and she always gets headaches. Sentence3: She complains that they are way to loud and don't listen. Sentence4: She asked the principal if she could teach at the high school level. Sentence5: The principal allowed her to switch to the junior year, she's happy.

Answer: I (myself), School, Principal, Sixth graders, Wife

Question: Sentence1: Jeff worked in an office. Sentence2: He liked his job but he had one insufferable co-worker. Sentence3: One day, the co-worker tried to destroy Jeff's work. Sentence4: Jeff caught him and reported it. Sentence5: Luckily, the co-worker was finally fired.

Answer:
Co-worker, Jeff