Teacher: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.
Teacher: Now, understand the problem? Solve this instance: Sentence1: Mark is a lifeguard in the summer time. Sentence2: One day while he was working a kid started struggling in the water. Sentence3: Mark dove into the water and swam to the kid. Sentence4: He brought the kid to the side of the pool where he could calm down. Sentence5: The kid thanked Mark for a job well done saving him.
Student:
Kid, Mark