A ChatGPT-based system was developed to enhance students’ oral Q&A skills at international conferences. By uploading their original papers to ChatGPT in the system, it generates oral questions to the students, who can practice Q&A. We examined six configurations for question generation: 1) whether reference papers should also be explicitly uploaded to the system, and 2) whether or not the questions should be generated for each keyword or each section in sequence. Surprisingly, all the students and teachers who participated in the experiment chose the simplest configuration – no explicit upload of reference papers and question generation from the entire scope of the paper. This finding led us to combine the simply-configured ChatGPT with a speech interface to create an interactive practice environment. Our system orally poses questions to a student about their papers, who responds verbally. After using this environment, all the participants strongly affirmed its effectiveness of practicing Q&A to attend future international conferences.