Read the story and answer the questions to test your comprehension.
Rollerblades are a mix between roller skates and ice skates. This design is otherwise called an in-line skate, since all the wheels are in one single line. The trademark "Rollerblade" has been around since 1983. When a user skates on in-line skates, they can often go faster than they would if they were using roller skates. Rollerblading is a very popular means of exercise.