['they', 'engage', 'Species', 'EmptyParameter', 'EmptyParameter']
['<PRP>', 'amalgamate-22.2', "Synset('category.n.02')", 'EmptyParameter', 'EmptyParameter']
At the time they engaged Species.
at the Synset('time_period.n.01') <PRP> engaged Synset('category.n.02').