2. Cai Lun has improved papermaking technology, using bark, hemp, rags and old fishing nets as raw materials to make paper, which improves the production efficiency of paper quality, expands the raw material sources of paper and reduces the cost of paper.
3. Bi Sheng created movable type printing, Wang Zhen created wooden movable type printing and invented wheeled typesetting board. Copper movable type appeared in Ming dynasty, followed by mimeograph, and now it is copied by magnetic properties.
Harvest: I learned about the profoundness of China culture and the wisdom of the ancient working people in China.
If it helps, I hope to adopt it, and I'd better get extra points! ! ! ! thank you