It is the generalization and innovation of students' basic content, and it is the basic content.

The first volume of the seventh grade is mainly the intermediary of primary schools. At the same time, it is not difficult to summarize the contents of new learning. In fact, it is not difficult to find that the seventh grade mathematics, especially the first volume, will not be very detailed, but in the second volume, it will be more detailed. It is also a summary of the last one. Otherwise, skip the first volume directly, and the students will not be able to keep up.

It's all about some uses of numbers. There will be some difficulties in seventh grade mathematics, but in these chapters, in addition to using seventh grade materials, it is to expand these numbers.