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: Matt's mom promised a surprise for him after school. Sentence2: He was excited all day. Sentence3: So excited that he wasn't paying attention during math class. Sentence4: When he didn't answer when called, he was given detention. Sentence5: Matt would have to wait longer to find out what was his surprise.

Answer: Matt, Matt's mom

Question: Sentence1: Warren didn't like beets and told his mom repeatedly. Sentence2: But as she never listened, he had some on his plate for dinner. Sentence3: He tried to give them to his dog. Sentence4: The dog sniffed them and walked away. Sentence5: Warren refused to eat the beets as his dog didn't want them either.

Answer: Dog, Mom, Warren

Question: Sentence1: Abby was a avid fan of basketball. Sentence2: However, Abby never got the opportunity to see a live game. Sentence3: Abby decided she would purchase tickets to watch a live game. Sentence4: In addition, Abby purchased a ticket for her friend to come as well. Sentence5: Abby could not wait to be in attendance for the basketball game.

Answer:
Friend, Abby