写实风格中年讲师白板前授课讲解职场培训场景人像照片

realistic photo, middle-aged male teacher with beard, wearing brown shirt and black tie, glasses, friendly smile, standing in front of whiteboard, pointing to whiteboard with right hand, explaining or asking questions, students sitting at desks, white background with brown and black accents, bright and clean classroom, warm interactive atmosphere, detailed, high resolution,8K, high-definition, photographic image