A person a intrument a the a knife is tuching in the a instument and budge
A man is demonstrating how to sharpen a pocket knife.
It appears to be that a man is demonstrating a gadget to sharpen a knife.
A man is showing a knife and how to sharpen the knife.
A person demonstrates a knife sharpening tool, stroking a knife against it.
A man is demonstrating how to sharpen a knife using a sharpening tool.
A person shows how to sharpen a knife that is worn down and dull.
A man has a sharpening tool and shows in a closeup how to sharpen his knife.
A man demonstrating the proper use of a knife sharpener to sharpen a knife blade.
A person was filing a knife over a file