(1) Long-term colonial rule has made Africa the continent with the lowest level of economic development in the world. After African countries gained political independence, their national economies have developed to varying degrees, but the industrial base of most countries is still very weak. One or several export-oriented agricultural and mining primary products have been unilaterally developed, becoming raw material suppliers and industrial products markets in developed countries, and the single economic form left over from history has not been fundamentally reversed;

(2) The prices of primary agricultural and mineral products produced in Africa are low, while the prices of imported industrial products such as fuel, chemicals, transportation equipment and machinery are high, so the import value is much higher than the export value;

(3) The industrial base of most African countries is still very weak. They unilaterally develop one or several export-oriented agricultural and mineral primary products and become raw material suppliers and industrial products markets in developed countries. This foreign trade structure is very unfavorable to the development of national economy;

(4) Protecting the natural environment, improving the production level of agriculture and animal husbandry, and controlling population growth; Develop diversified economy, cultivate scientific and technological talents, improve the cultural quality of the people and promote agriculture through science and technology.

So the answer is: (1) Long-term colonial rule has made Africa the continent with the lowest level of economic development in the world. After African countries gained political independence, their national economies have developed to varying degrees, but the industrial base of most countries is still very weak, and one or several export-oriented agricultural and mining primary products have been unilaterally developed, becoming raw material suppliers and industrial products markets in developed countries, and the single economic form left over from history has not been fundamentally reversed;

(2) The prices of primary agricultural and mineral products produced in Africa are low, while the prices of imported industrial products such as fuel, chemicals, transportation equipment and machinery are high, so the import value is much higher than the export value;

(3) The industrial base of most African countries is still very weak. They unilaterally develop one or several export-oriented agricultural and mineral primary products and become raw material suppliers and industrial products markets in developed countries. This foreign trade structure is very unfavorable to the development of national economy;

(4) Protecting the natural environment, improving the production level of agriculture and animal husbandry, and controlling population growth; Develop diversified economy, cultivate scientific and technological talents, improve the cultural quality of the people and promote agriculture through science and technology.