Read this passage: I'm normally a kind and understanding person, but my wedding is my special day. Therefore, I'm going to say this just once: Don't buy me a gift that's not listed on my registry. And no, I don't care that the cheapest items on the registry are $500. You have time to save up, and it's a special casion. You still want to be my friend, don't you? What implicit theme does this passage most clearly develop?