sentence: Two men are rollerblading on a sidewalk of a quiet street. sentence:  There are four young men and women rollerblading on a street with lots of trees. sentence:  There are some professionals rollerblading in a stadium and on a sidewalk by a fountain. sentence:  One man jumps over a chained sidewalk while rollerblading. sentence:  A couple is rollerblading on a sidewalk and another man is jumping over a barricade onto a sidewalk. sentence:  Several people are rollerblading on the sidewalk. sentence:  There are some people competing in a rollerblading competition. sentence:  There are some men rollerblading through streets at very high speed. sentence:  Some of them are climbing stairs with their roller blades. sentence:  Some men are rollerblading through a busy city and on bridges. sentence:  There is a group of young children rollerblading together. sentence:  One man leaps over a wall while rollerblading. sentence:  One person dives straight into water as he comes rollerblading at high speed. sentence:  People are rollerblading through the city, going down the stairs and even on sidewalks. sentence:  Two boys jump into an S shaped structure while rollerblading. sentence:  Two people are doing figure eights on a bridge as they roller blade. sentence:  One person goes steadily while rollerblading.