It is a leap from understanding plane graphics to understanding three-dimensional graphics, and there must be a process. It is a good method for some students to make some geometric models of space and observe them repeatedly, which is conducive to establishing the concept of space. Some students will observe and ponder some three-dimensional figures in their spare time, judge the relationship between lines, lines and planes, and explore various angles and vertical lines, which is also a good way to establish the concept of space. In addition, using graphs to represent concepts and theorems, and "proving" theorems and constructing graphs of theorems in your mind are also very helpful to establish spatial concepts.

Second, we should master basic knowledge and skills.

We should express concepts, theorems and formulas in three forms: graphics, words and symbols, and constantly review what we have learned before. This is because the contents of solid geometry are closely related. The former is the foundation of the latter, which not only consolidates the former, but also develops and popularizes the former. When solving problems, write specifications. For example, when a parallelogram ABCD is used to represent a plane, it can be written as a plane AC, but the word plane cannot be omitted; To write the basis for solving problems, whether it is a calculation problem or a proof problem, you should not take it for granted or rely entirely on intuition; Written proof questions, written known and verified, drawing; When using the theorem, it must be clear that the conditions that the topic satisfies the theorem correspond to each other. It's impossible to know without writing it. Learn to use diagrams (drawing, decomposition diagram, transformation diagram) to help solve problems; It is necessary to master the basic methods of finding various angles and distances and the basic methods of reasoning and proof-analysis, synthesis and reduction to absurdity.

Third, we should constantly improve our abilities in all aspects.

Propose a proposition by connecting with practice, observing models or analogizing plane geometry conclusions; Don't easily affirm or deny the proposition, but use several special cases to test it. It is best to give a negative example and definitely prove it. The content of Euler formula is given in the form of research topic, from which we can experience and create mathematical knowledge. We should constantly structure and systematize what we have learned. The so-called structure refers to the understanding and organization of knowledge from the whole to the part and from top to bottom, and to understand the ideas and methods implied in it. The so-called systematization is to gather parallel problems, vertical problems, angle problems, distance problems, uniqueness problems and other similar problems, compare their similarities and differences, and form an overall understanding of them. Firmly grasp some concepts that can control the overall situation and the whole organization, and use these concepts to control the connection between the known knowledge that is occasionally touched or not yet aware of the obvious relationship, so as to improve the overall concept.

Pay attention to accumulating strategies to solve problems. For example, the problem of solid geometry is transformed into a plane problem, or the problem of finding the distance from a point to a plane, or the problem of finding the distance from a straight line to a plane, and then it is transformed into the problem of finding the distance from a point to a plane; Or become a volume problem. We should constantly improve the level of analyzing and solving problems: on the one hand, from the known to the unknown, on the other hand, from the unknown to the known, we should seek the connection point of positive and negative knowledge-an internal or definite mathematical relationship. We should constantly improve the level of reflective cognition, actively reflect on our own learning activities, from experience to automation, from sensibility to rationality, deepen our understanding of theory and improve our ability and creativity in solving problems.