Final answer:
Besides religious ceremonies, Sumerians used ziggurats primarily for administrative functions, serving as economic redistribution centers and hubs for managing resources within the cities.
Step-by-step explanation:
The Sumerians used ziggurats for various functions beyond religious ceremonies. One of the key additional uses of ziggurats was for administrative functions. As massive and impressive structures in the center of Sumerian cities, they served as administrative centers where civic and religious officials collected and redistributed agricultural goods as a form of tax. Scribes kept meticulous records of these transactions in cuneiform. This economic role made the ziggurat a vital hub in the city for the management of resources and the political authority of religious leaders operating on the gods' behalf, thus intertwining the economic and administrative aspects of Sumerian society.