During the busy farming season, the tractor hauled the stone rollers to the threshing ground, carried straw and grain, ploughed and sowed the fields, and when there was a drought it pumped water to irrigate the land. It also served as a means of transportation during holidays and festivities, and in idle times it could even haul bricks and sand to make some money—these were the basic functions of the tractor.
Not only that, but the tractor could also be modified, like Ma Yongming's construction crew's excavator and Douzi Car, which were made just like that.
Beyond that, serving as a power source for some machinery was also a basic use for tractors. These days, quite a few agricultural machines could be powered by tractors, like the threshing machine being used in the field right now.