1. Be fully prepared: Make sure that you are very familiar with the content of your paper before replying. This includes research background, methods, data and results. At the same time, I know the latest progress and related literature in my research field.

2. Predict questions: imagine the questions that the judges may ask and prepare the answers in advance. This can help you to be more confident in your defense.

3. Concise and clear: Try to be concise and clear when answering questions. Avoid using too complicated terms or too many details to avoid confusing the judges.

4. Keep calm: In the process of defense, you may encounter some unexpected problems or challenges. Keep calm and don't panic, which will help you to deal with the problem better.

5. Appropriate use of body language: When answering questions, appropriate use of body language, such as nodding and smiling, can increase your persuasiveness.

6. Pay attention to time control: in the process of defense, pay attention to controlling your own speech speed to ensure that you can complete the answer within the specified time.

7. Stay confident: Even if you are not sure about a problem, try to show confidence. This will make the judges feel that you are a trustworthy researcher.

8. Learn to divert attention: If you encounter a difficult problem, you can try to shift the topic to an area you are already familiar with, or ask the judges to give you some time to think.

9. Listen to the judges' opinions: When answering the judges' questions, listen carefully to their opinions and suggestions. This will help you better understand their views and improve them in future research.

10. Conclusion: At the end of the defense, you can briefly summarize your own views and thank the judges for their time and suggestions. This will make a good impression on the judges.