Four girls are walking down the sidewalk.
Four girls walk down a sidewalk.
Four girls roll under a sidewalk.
Skiiers walking up the hill.
A kid is playing.
A snowboarder performs a trick in the half pipe.
The steps and practices in this guide have largely been published elsewhere, too.
The main oxygen system of Mir has had repeated failures.
On the other hand, you might enjoy using secondary roads to discover the country.