Given the task definition and input, reply with output. 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: When I walked into my math class, it was quiet. Sentence2: Everyone took out their pencils and scantron accept myself. Sentence3: I was confused and asked my teacher what we're doing today. Sentence4: She says that were taking an exam. Sentence5: My heart started to beat fast since I didn't study.
I (myself), Everyone, Math class, My teacher