The sylph changed direction, and began to bob about.
There was a sylph moving around.
The sylph was only able to travel in perfectly straight lines, and moved at a perfectly steady height.
A man is swimming.
Jon hid inside the cave instead of fighting.
A man is playing scrabble.
Glad to have talked to you Jim.
They seek to overcome the other using pure physical strength.
It makes no sense to make the law complicated.