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

I was anesthetized using laughing gas at the dentist.

Nitrogen monoxide is a cause of air pollution.

Nitrogen dioxide is a cause of air pollution.

I will work using this laptop.

For the surgery, the doctor administered anesthesia to me.

She called him by his name.

He is called the smartest in the class.

He often gets treated to dinner by his friends.

Nitrogen makes up about 78% of the Earth's atmosphere.