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.

Ex Input:
Sentence1: Joe was bit by a cat when he was very young. Sentence2: Since then, he has always been scared of cats. Sentence3: One day at school, a cat came up to him and played with him. Sentence4: Joe had a lot of fun with the cat. Sentence5: Now, Joe is not scared of cats.

Ex Output:
Joe, Cat

Ex Input:
Sentence1: My wife used the vacuum cleaner today. Sentence2: It is very noisy. Sentence3: Our cat hates it. Sentence4: She hid under the bed for an hour after the vacuuming stopped. Sentence5: She slowly came out and is fine now.

Ex Output:
Our cat, My wife

Ex Input:
Sentence1: We celebrated July 4th. Sentence2: We cooked out on the grill. Sentence3: We also shot fireworks. Sentence4: Our friends had us out on the boat. Sentence5: It was a great way to celebrate our independence.

Ex Output:
Friends