A young man wears a helmet and protective clothing as he races his dirt bike through a muddy track .
It is probably the case that a young man in a bike race rides his dirt bike along a muddy track .
It is probably the case that a young man in a bike race rides his dirt bike along a muddy track .
We doubt that a young man in a bike race rides his dirt bike along a muddy track .
A young man in a bike race rides his dirt bike along a muddy track .