It is impossible that Greg is gray. It is certain that Lily is a lion. There is a very good chance that John left the football. It is impossible that if either Greg is gray, or Lily is a lion, then Brian is a frog. It is certain that if Greg is gray, or Lily is a lion, then Mary went to the garden. It is impossible that if John left the football, or Greg is gray, then Jeff discarded the apple.
It is impossible that jeff discarded the apple, or Greg is gray.
It is impossible that jeff discarded the apple, or Greg is gray.
It is certain that jeff discarded the apple, or Greg is gray.
Jeff discarded the apple, or Greg is gray.