['she', 'hear', 'hiss', 'EmptyParameter', 'EmptyParameter']
['<PRP>', 'discover-84', "Synset('sound.n.04')", 'EmptyParameter', 'EmptyParameter']
But then she heard a hiss from the ventilation duct.
but then <PRP> heard a Synset('sound.n.04') from the Synset('organic_process.n.01') Synset('passage.n.03').