Have most famous operas been adapted?

It should be said that China's traditional opera stories all come from folk tales, which are passed down in an orderly way in the literary history of China. From legend to Tang legend, to Song edition, to Yuan Zaju, to Ming and Qing operas, it has been gradually processed, adapted and passed down to this day. Every processing and adaptation will be branded with that era.

For example, The Romance of the West Chamber was originally a local legend. In the Tang Dynasty, Yuan Zhen was named Yingying Biography, and Dong Jieyuan in the Jin Dynasty recorded it in The West Chamber. In Yuan Dynasty, Wang Shifu made five Romances of the West Chamber, which were adapted into Romance of the West Chamber and Beijing Opera Matchmaker in modern times, and other operas were also adapted accordingly. Their plots are generally similar, but they are different and have their own emphasis.