This is why, from a biologist's point of view, trying to define "races" is impossible if not pointless.
Witzig's photos would have been impossible if not for his profound familiarity with, and reverence for, the coastal waters of Australia.
"It's impossible, if not misdirected, to try and make a work of art look the way it did when it was new," she insisted.
These kinds of stories are impossible if not for people like your relatives, people brave and gracious enough to let a gringo stranger into their living rooms, their kithchens, their entire lives.
Conducting a broad literature search to capture every single potentially relevant paper would have been impossible if not inappropriate, especially since precise estimation is not the objective of such a review.
X-ray for movies would be impossible if IMDB weren't part of the Amazon family.
It is barely possible to get through if you follow it and it may be impossible if you don't".
Working well with someone means being relaxed with them - and that is impossible if you're not sure whether they're trying to seduce you or not.
Otherwise, a stable transfer of power is impossible (if it isn't already).
It was a reasonable hypothesis, but proving it might've been impossible if it weren't for a lucky coincidence.
