context: A man perched on a row of aquariums is using a net to scoop a fish from another aquarium.
hypothesis: It is certain that a man is standing by the aquariums.
valid_hypothesis: It is certain that a man is standing by the aquariums.
invalid_hypothesis: It is probably not the case that a man is standing by the aquariums.
hypothesis_assertion: A man is standing by the aquariums.