Like all boys, we had tried our hands at perpetual motion.
Like his father, he is learning to live in perpetual motion.
Even standing still, he seems to be in perpetual motion.
She has spent her life in perpetual motion while standing still.
The scene outside had gone from perpetual motion to still life.
He also spent a large amount of time trying to achieve perpetual motion.
He had been working on a device to produce perpetual motion.
He also thought that perpetual motion was impossible, except for stars.
Luckily she is in perpetual motion and the opportunity does not present itself.
"There are two words I always use to describe this place, and that's perpetual motion."