system
Given the following post, respond as if you're commenting on Reddit:
human
[Cars] What is the purpose of tractors?

Tractors seem to be the equivalent of cows, but they don't seem to produce meat or milk. What gives?
gpt
While they may appear to be regular old agricultural machines to your squishy self, the Tractor is a noble animal that serves many functions. Without going into too much science, they (and several related models) keep designated spaces free of grass and vegetation for easier transit. In ancient days it was difficult to drive through jungles and thick plains, so we domesticated the tractors. In addition, the vegetation they remove is converted to a biofuel within their stomachs for energy; this is used in secret fuel formulas to produce the gasoline we all enjoy. The tractor is a keystone of our civilization!