Some people with black belts , or black and red belts , are performing martial arts on a green mat .
It is improbable that several martial artists were fighting to bring their belt colors to the next level .
There is a better than even chance that several martial artists were fighting to bring their belt colors to the next level .
It is improbable that several martial artists were fighting to bring their belt colors to the next level .
Several martial artists were fighting to bring their belt colors to the next level .