A long dark-haired man sitting on the grass with a guitar in his lap in front of a blue sky.
A man with short hair dancing outside while playing the flute.
Sitting and dancing are different actions, and a guitar and flute are different instruments.
A long  dark haired and a man with short hair cannot be the same.
A man cannot have both long hair and short hair at the same time. He cannot be sitting and dancing at the same time. Finally, he cannot play the guitar and flute simultaneously.