sentence: A woman is standing by a bathroom door talking. sentence:   The same woman is now seen on a stationary bicycle teaching a spin class. sentence:  Several other people in the class can be seen on stationary bicycles in the mirror behind the instructor. sentence:   The woman is then shown on the ground demonstrating an exercise. sentence:  The spin class is shown again still in progress. sentence:  The instructor then does floor exercises again with the class following along. sentence:   The instructor and the class finish on the bikes again.