Title: The Key to Interesting Talks The key is an all-purpose tool. It can open many different locks and enter many different rooms. In novels, keys often have many uses. Here are some common plots: The key is one of the most commonly used tools of the protagonist. It can open all kinds of locks, including locks on trees, locks on walls, locks on doors, and so on. The protagonist often used his intelligence to open various locks with keys to solve various problems. The key could also become a symbol of love for the protagonist. In some novels, the protagonist might use the key to express his feelings for someone, such as using the key to open the other person's lock to express his feelings. The key could also be a turning point in the character's fate. In some novels, the protagonist might encounter some locks, such as a lock locked in fate, which could only be opened with a key. Once the protagonist opened this lock, his fate would change drastically. The 4 keys could also become one of the character's props. In some novels, the protagonist might use keys to make tools such as lockpicking tools, locksmith tools, and so on. These tools could help the protagonist solve various problems. In short, the key has a wide range of applications in the novel. It is not only a tool, but also a symbol, a tool to express emotions, a tool to change fate, a tool to make tools.