A caucasian man wearing red plaid bottoms and a black vest with large buttons with a tattoo on one arm has an upside down unicycle balancing on his mouth.
A man is riding a unicycle.
If the man is balancing the unicycle on his mouth, he cannot be riding the unicycle.
A man cannot be balancing a unicycle  on his mouth and riding unicycle at the same time.
If the rider is balancing the unicycle on his mouth, it means he is not riding it.