A boy is doing a skateboard trick on the boardwalk .
There is a very good chance that a skateboarder is practicing new techniques and tricks with his skateboard .
There is a very good chance that a skateboarder is practicing new techniques and tricks with his skateboard .
It is unlikely that a skateboarder is practicing new techniques and tricks with his skateboard .
A skateboarder is practicing new techniques and tricks with his skateboard .