In vocational education, students have to develop competences for reflection to self-regulate their development during their career. Students' reflection can be supported by teachers interacting with students and giving them prompts. In this study, 46 videotaped feedback dialogues of 23 teachers and their individual students were analysed. A total of 16 teachers participated in a training programme and 7 teachers formed a control group. The study aimed to investigate teachers' questions and responses and students' reactions, and the effects of the training programme. Analysis showed that, in the post-test, the trained group used a broader repertoire than the control group. The trained group, on average, used more hybrid prompts, deep reasoning questions, and prompt responses, which potentially stimulate students to elaborate and reflect.