['alien', 'step', 'attack', 'EmptyParameter', 'EmptyParameter']
["Synset('entrant.n.03')", 'run-51.3.2', "Synset('disapproval.n.02')", 'EmptyParameter', 'EmptyParameter']
The aliens have stepped up their attacks.
the Synset('entrant.n.03') have stepped up <PRP> Synset('disapproval.n.02').