Thus, simultaneous NOx and SO2 emission reductions are critical.
Reducing NOx and SO2 at the same time is essential.
Reducing NOx and SO2 at the same time is not likely.
A man is standing on stairs.
Older woman playing piano.
The palace has 2000 rooms and only a small amount of them are open for viewing to tourists.
A woman is dangling from a metal structure.
The hill has a fallen skier on it.
You are quite knowledgeable that it's due to it being so small.