sentence: A man demonstrates how to rollerblade safely by exhibiting and demonstrating rollerblade safety gear while in a public park. sentence:   The man begins by rollerblading down a long walk way and then  sitting on a bench outdoors and talking to the cameras. sentence:   The man then demonstrates how to strap on roller blades. sentence:   The man then showcases a white helmet, strapping it on and then rollerblading in an park among the people.