There is a very good chance that Brian is a rhino. Chances are about even that Mary went to the office. It is impossible that Bernhard is white.
There is a very good chance that either Brian is a rhino, or Bernhard is white.
There is a very good chance that either Brian is a rhino, or Bernhard is white.
It is unlikely that either Brian is a rhino, or Bernhard is white.
Either Brian is a rhino, or Bernhard is white.