It is unlikely that Emily is a cat. It is unlikely that Gertrude is a mouse. There is little chance that John went to the garden. It is unlikely that if either John went to the garden, or Emily is a cat, then Mary left the football. It is probably not the case that if Emily is a cat, or John went to the garden, then Lily is white. Chances are about even that if John went to the garden, or Emily is a cat, then Brian is yellow.
It is highly likely that either Brian is yellow, or Mary left the football.
It is improbable that either Brian is yellow, or Mary left the football.
It is highly likely that either Brian is yellow, or Mary left the football.
Either Brian is yellow, or Mary left the football.