Abstract: This paper briefly introduces the relevant contents of online and offline teaching, expounds the necessity of developing online and offline teaching, and through analyzing the problems existing in online and offline teaching at present, in order to change the traditional classroom teaching mode, make clear the importance of the combination of online and offline teaching, change the old teaching concept, and give full play to the role of modern science and technology, using modern education technology to carry out high-efficient on-line and off-line mixed teaching, arouse students' study interest, realize the maximum of teaching benefit, thus promote the sustainable development of modern education in our country, and meet the demand of quality education reform.

Key words: Online teaching, Offline teaching, Effective convergence, Measures, Teaching efficiency