1. Change the subject: You can change the subject and ask the other person some irrelevant questions, such as "Which movie do you like best?" Or "Do you have any new hobbies recently?" This will shift the focus away from your predecessor.

2. Lighthearted and humorous answer: You can answer this question in some humorous or light-hearted ways, such as "My predecessor? Oh, he has moved to the moon now. " Such an answer can solve the embarrassment and let the other person know that you don't want to talk about this problem.

3. short and polite answer: if the other person keeps asking about your predecessor, you can answer simply and politely, such as "we have some past, but now I am more concerned about our future." Such an answer is not only polite, but also conveys your attitude and position.

4. Express your feelings directly: If the other person keeps asking your ex and you don't want to answer, you can express your feelings directly, such as "I don't want to talk about my past, I hope we can pay more attention to our present and future." Such an answer can let the other person know what you think, and at the same time avoid unnecessary arguments.

No matter which way you choose, you should remain confident and calm, and don't let this question affect your emotions and relationships.