In order to meet the needs of students' technical skills growth and improve students' comprehensive professional ability, this project does the exploration and practice of the second classroom, and the "four modes" focusing on the core professional ability is proposed. This model includes skills training class, technology research class, innovation & entrepreneurship class and apprenticeship class. Students' four abilities are cultivated: skills practice, technology research, innovation & entrepreneurship, and job adaptation. Teaching and research ability of teachers and technical skills of students have been greatly improved through the second classroom teaching of this model.