Set up two units for review. Through the dialogue between Chinese teachers and foreign teachers, consolidate what you have learned and study separately. The content of situational dialogues arranged in each class spirals up step by step according to the difficulty, interest and practicality. Mastering daily conversations in different scenes, mastering authentic grammar and language expression through imitation and practice, and dribs and drabs of the country after each scene can also let readers know some foreign human geography and customs. And arrange appropriate oral and translation exercises after the supporting study manual of each lesson, so that you can consolidate your knowledge in time.