There is a very good chance that John got the milk. It is impossible that Brian is gray. We believe that Lily is green.
It is probably not the case that either John got the milk, or Lily is green.
It is probably not the case that either John got the milk, or Lily is green.
It is highly likely that either John got the milk, or Lily is green.
Either John got the milk, or Lily is green.