Nitrogen monoxide is a cause of air pollution.

The First International was an international organization of workers.

His shoes are a symmetrical pair, perfectly matching left and right.

His painting expresses pure beauty.

He was walking around the room wearing only underpants.

I reserved a single room.

I was filled with his kindness.

His kindness made me have a lump in my throat.

He accepted the proposal without dispute.

He vowed to live through this world and the next with the spirit of once-in-a-lifetime encounter.