You are absolutely right! Sulfur oxides, particularly sulfur dioxide (SO2) and sulfur trioxide (SO3), are primarily produced by burning materials that contain sulfur.

Here's a breakdown:

* Fossil fuels: Coal and oil often contain sulfur as an impurity. When these fuels are burned for energy, the sulfur reacts with oxygen in the air, forming sulfur dioxide (SO2).

* Industrial processes: Some industrial processes, like the production of metals, also release sulfur dioxide as a byproduct.

* Volcanic eruptions: While not a direct result of burning, volcanic eruptions are a natural source of sulfur dioxide and other sulfur oxides.

Important note: Sulfur dioxide is a major air pollutant that contributes to acid rain, respiratory problems, and other environmental issues.