1·This all changed, thanks to an man named Cai Lun.
幸得一个叫蔡伦的人，这一切都改变了。
2·1,900 years ago, Cai Lun improved the paper-making process.
1900年前，蔡伦改进了造纸工艺。
3·Paper was first invented about two thousand years ago in China by Cai Lun.
大约两千年前，中国的蔡伦首次发明了纸。
4·Cai Lun began experimenting with many different materials and different methods to turn those materials into paper.
蔡伦开始尝试许多不同的材料和不同的方法来把这些材料变成纸。
5·Paper, one of the four greatest inventions in ancient China, was invented by Cai Lun about 2, 000 years ago.
纸是中国古代四大发明之一，大约在2000年前由蔡伦发明。
6·Today, Cai Lun is considered a national hero in China.
今天，蔡伦在中国被视为民族英雄。
7·Cai Lun invented paper around 2, 000 years ago in China.
大约2000年前，蔡伦在中国发明了纸。
8·It was invented by Cai Lun.
是蔡伦发明的。
9·It is widely accepted that paper was invented by Cai Lun in the Eastern.
普遍认为纸由蔡伦在东汉时期发明。
10·It is widely accepted that paper was invented by Cai Lun in the Eastern Han.
普遍认为纸由蔡伦在东汉时期发明。