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.
Problem:Sentence1: Mark woke up on Monday morning with a terrible cold. Sentence2: The worst part of Mark's cold was his awful cough that wouldn't stop. Sentence3: Mark got in the car and drove to the local drug store. Sentence4: Mark found a bottle of cough syrup, and it was even on sale! Sentence5: Mark took the suggested dose from his doctor and felt much better.
Solution:
Doctor, Mark