TASK DEFINITION: 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: Ana needed gas in her car. Sentence2: But the prices in her town were so high! Sentence3: She took a drive out the the reservation. Sentence4: There, gas was almost a dollar cheaper. Sentence5: Ana filled her tank at the reservation!

SOLUTION: Ana

PROBLEM: Sentence1: Tom was walking around. Sentence2: He found a wallet on the ground. Sentence3: It was completely empty. Sentence4: Tom thought it was a nice looking wallet. Sentence5: He kept it for himself.

SOLUTION: Tom

PROBLEM: Sentence1: Jeff was watching a car racing movie. Sentence2: And afterwards, he felt like using his own car for races. Sentence3: He sped down the freeway one night. Sentence4: But he was caught be a police officer and issued a speeding ticket. Sentence5: Jeff had to do 50 hours of community service.

SOLUTION:
Police officer, Jeff