Subjective aspect: Contemporary people's educational awareness is increasing day by day, and many countries have promulgated the Compulsory Education Law (China 1986) to implement free compulsory education. Many people of insight have clearly realized that whoever has mastered science and technology today will have mastered tomorrow's victory. The gap between countries, on the surface, is an economic gap, but in essence, it is a gap in science and technology and talents, and in the final analysis, it is a gap in education. It can be said that today's education is tomorrow's technology and the economy the day after tomorrow. In view of this, many countries regard the development of education as a top priority and attach great importance to it at all costs, such as extending the years of compulsory education, increasing investment in education and encouraging outstanding talents to engage in education. Some developing countries, in particular, are suffering from "being beaten behind". In order to revitalize the national economy and enhance the national strength by cultivating a large number of outstanding talents, they attach great importance to the development of education.

Objectively speaking, strong economic backing provides rich material guarantee for education first. In the early 1960s, the world economy provided the possibility for countries to spend huge amounts of money on education. Abundant capital investment and the adoption of advanced educational facilities have greatly accelerated the development of education, making it quickly ahead of other social undertakings and becoming the "locomotive" of the development of human civilization. In addition, due to the changes and development of science, culture and education itself, it first provides enough content for education. It is reported that the most authoritative biology textbook in the world will be rewritten every five years [7]. The cycle of world knowledge updating is getting shorter and shorter, from 80 to 90 years in18th century to 30 years in the early 20th century, and then to15th year in the last 50 years. Now the knowledge updating cycle of some disciplines has been shortened to 5- 10 years [8]. The accelerated updating and aging of knowledge forces the educational content to make corresponding changes. Due to the great development of educational science and psychological science, it constantly provides new theoretical basis and theoretical guidance for educational practice, making educational methods, means, content and structure more scientific and systematic.