帮忙看看这个句子有错嘛.
问题描述：
帮忙看看这个句子有错嘛.
Shaanxi Liquan Country discovered about two tons of ancient coins which made and used in dynasties of Tang Song and Yuan.They’re in the museum for study and show.This is an important discovery for the study of China’s ancient coins.
答
"which were made and used"
in Tang Song and Yuan dynasties