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: Greta had noticed her son was having trouble focusing in school. Sentence2: Greta took her son to the doctor. Sentence3: The doctor diagnosed the boy with ADHD. Sentence4: The doctor prescribed medicine for him. Sentence5: Greta's son now focuses much better in class.

A: Greta, Greta's son, The doctor
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Q: Sentence1: Mary woke up Monday morning with a headache. Sentence2: She knew that she had to go to work in just one hour. Sentence3: After she drank her morning coffee she set out to work. Sentence4: Upon her arrival, her boss told her that her co-worker called in sick. Sentence5: That meant that Mary would have to pull a double shift!

A: Boss, Mary, Co-worker
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Q: Sentence1: Frank hated wearing old socks. Sentence2: He bought a drawer full of new ones. Sentence3: They were so comfortable! Sentence4: He kept the socks on all the time. Sentence5: Having new socks made him wish for new underwear, too.

A:
Frank
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