Thus, for example: No snakes are mammals and No mammals are snakes , like Some carnivors are birds and Some birds are carnivors are each the converse of the other.
(No snakes; are; mammals and No mammals) (Some carnivors; are; birds) (Some birds; are; carnivors) (Some carnivors; are; each the converse of the other)
No snakes Some carnivors Some birds Some carnivors
are are are are
mammals and No mammals
birds
carnivors
each the converse of the other