请将下面这段话翻译成英文：
在古代，著作和铭文(inscription)通常写在竹片或丝绸上。但丝绸昂贵，竹片太重，使用起来都不方便。后来蔡伦开创了用树皮造纸的方法。传统上人们认为 他是纸张和造纸术的发明者。尽管公元前2世纪中国就已经有了早期的纸，但蔡 伦促成了纸张的首次重大改进，并通过添加至关重要的新材料使造纸过程标准 化。蔡伦发现了造纸材料的组合方式，发明了造纸术。这项发明使蔡伦闻名于世， 甚至使他在有生之年就已经得到了认可。
参考答案:
In ancient times, writing works and inscriptions were generally written on :tablets of bamboo or on pieces of silk. But silk being costly and bamboo heavy, they were both not convenient to use. Then Cai Lun initiated the method of making paper with the bark of trees. Traditionally, he is regarded as the inventor of paper and the technique of papermaking. Although early forms of paper had already existed in China since the 2nd century BC, he fostered the first significant improvement and standardization of papermaking by adding essential new materials into papers composition. Cai found the composition of paper and invented the technique of papermaking. Cai was reputed for this invention in the world, and even in his own lifetime he was already given recognition for it.
1.丝绸昂贵:可翻译为silk being costly。
2.开创了用树皮造纸的方法:“开创”可用initiate表达；“树皮造纸”可翻译为 making paper with the bark of trees。
3.首次重大改进:可翻译为the first significant improvement。.
4.添加至关重要的新材料使造纸过程标准化:“至关重要的”可翻译为essential; “使造纸过程标准化”可用 foster standardization of papermaking表达。
