Abstract: In the process of acquisition, learners have two levels of development: one is the existing level, which refers to the level that can be achieved independently before acquiring new knowledge; the other is the level that can be achieved, which is the potential that can be excited to the next existing level through teaching stimulation. In the middle of them is "Proximal Development Zone". During the process of carrying out the model of Mixing Teaching, teaching intervention plays a particularly important role in the zone of proximal development. The aim of surpassing Zone of Proximal Development to next developing level can be realized by Online + Offline intervention; and the maximization of the teaching effect can also be done as well.

Key words: Acquisition, Proximal development zone, Mixing teaching, Teaching intervention, "Online + Off-line" intervention