The Nature of Ki no Nagare
The way I was taught (or, at least, remember being taught), kihon was static and ki no nagare was in movement. Ki was always ambiguously translated as energy.
A lot has changed over the years.
I have found these distinctions to be totally insufficient.
I have begun to think that spirit or life-force is a much better way to look at ki. And ki no nagare should be to go with the flow of that, which I might add is very different than going with the flow of movement. (I also now realize that kihon is more properly basics or fundamental.)