['it', 'purr', 'EmptyParameter', 'cat', 'like']
['<PRP>', 'animal_sounds-38', 'EmptyParameter', "Synset('drug.n.01')", 'like']
It is purring like a contented cat.
<PRP> is purring like a Synset('contented.a.01') Synset('drug.n.01').