chocolate

One of my students and I are well used to each other's ways. He came back to Japan after a short trip to Europe with chocolates one day. He said he would give me some of them. I said, "Oh, thank you, I would like to give them to my children." He asked, "How many children did you have, Mrs. Shiomi?" Then I came up with a very good idea. I said, "Eight". The student stopped his movement and looked at me in my face. After a second, he burst into laughter and gave me six. But I didn't know why six.