When Cao Cao gave Yu Xun an empty box, he actually gave Yu Xun a crossword puzzle. Cao Cao has a precedent for crossword puzzles. Once writing movable type on the door, Yang Xiu guessed the word "kuo" and once wrote the word "one crisp" on the pastry box. As a result, Yang Xiu shared it with others. Cao Cao asked the reason. Yang Xiu explained: "One person, one bite!"

Now look at an empty box that Cao Cao sent to Yu Xun. The reason why Yu Xun committed suicide lies in the word "box". Open the box, because the box is empty and there is nothing in it, so remove the word "mouth" in the middle. What's left? The host came down from the plate and went through the middle. A person's neck is horizontal, is it like suicide? In ancient times, the characters on the following vessels were used to hold the blood of sacrificial animals or sacrificial animals. Therefore, after solving this puzzle, Yu Xun committed suicide.

There are many crossword puzzles in the Three Kingdoms, typical of which is Wei Yan's dream interpretation. Wei Yan dreamed that there were two horns at night. The angle is serrated, so it can be used under the knife!