It is probably the case that Greg is gray. It is probably not the case that John went to the office. There is a very good chance that Mary got the apple.
There is little chance that either John went to the office, or Greg is gray.
There is a better than even chance that either John went to the office, or Greg is gray.
There is little chance that either John went to the office, or Greg is gray.
Either John went to the office, or Greg is gray.