This person is performing a trick in skateboarding competition , with people watching in the background .
It is impossible that a person is practicing on his skateboard , alone in his backyard .
It is impossible that a person is practicing on his skateboard , alone in his backyard .
There is a better than even chance that a person is practicing on his skateboard , alone in his backyard .
A person is practicing on his skateboard , alone in his backyard .