This factory is emitting a large amount of sulfur dioxide.

Carbon monoxide is a colorless, odorless gas, and it is dangerous to inhale.

Nitrous oxide, also known as laughing gas, is used for anesthesia.

Silicon dioxide is a major component of glass and ceramics.

Nitrogen monoxide is a cause of air pollution.

Nitrogen dioxide is a cause of air pollution.

He feels it takes time to acquire new skills, but Rome wasn't built in a day.

After many years of effort, he was finally able to achieve his goal and make a name for himself.

Nitrous oxide is one cause of air pollution.

He was able to achieve career success and fame after much hardship.