A man in a black shirt appears to be jumping in the air holding two boards with a sign saying `` stomp '' in the background .
It is certain that a man jumps in the air in front of a sign .
It is certain that a man jumps in the air in front of a sign .
It is improbable that a man jumps in the air in front of a sign .
A man jumps in the air in front of a sign .