You will be given a definition of a task first, then some input of the task.
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: Today's a big day for me. Sentence2: It's the last day that I can take my final test. Sentence3: this test isn't so hard I thought as I was taking it. Sentence4: I was so nervous as I waited for my result. Sentence5: The teacher called me into the room and showed me my perfect score.
Output:
I (myself), Teacher