sentences:  When used in the context of Chinese history, especially China before the Tang Dynasty, the word "prefecture" is used to translate "xian" ().This unit of administration is translated as "county" when used in a contemporary context, because of the increase of the number of "xian" and the decrease of their sizes over time in the Chinese history.In the context of Chinese history during or after the Tang Dynasty, the word "prefecture" is used to translate "zhou" (Wade–Giles "chou" (), another ancient unit of administration in China, equivalent to the modern "province".