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.

Sentence1: Kathie fell from her bicycle. Sentence2: She bumped her head pretty hard on the ground. Sentence3: Kathie stood up dazed. Sentence4: A stranger escorted her to a hospital. Sentence5: Kathie was treated for a mild concussion.
A stranger, Kathie

Sentence1: Shelly wanted to make a music video for his new song. Sentence2: He got some friends together and hired a host of extras. Sentence3: They danced on cars that they parked in a city. Sentence4: The video was a moderate success. Sentence5: Shelly saw a slight bump in downloads of his song.
Extras, Friends, Shelly

Sentence1: Tim had his phone in class. Sentence2: He forgot to put it on silent. Sentence3: A friend kept trying to text him. Sentence4: Tim was caught fiddling with it. Sentence5: The teacher took it away for the day.
Tim, Teacher, A friend