['he', 'discover', 'EmptyParameter', 'EmptyParameter', 'EmptyParameter'] ['Archer', 'occupy', 'EmptyParameter', 'alien', 'by'] ['Tpol', 'occupy', 'EmptyParameter', 'alien', 'by']
['<PRP>', 'discover-84', 'EmptyParameter', 'EmptyParameter', 'EmptyParameter'] ['<PERSON>4', 'amuse-31.1', 'EmptyParameter', "Synset('entrant.n.03')", 'by'] ['<PERSON>5', 'amuse-31.1', 'EmptyParameter', "Synset('entrant.n.03')", 'by']
He eventually discovers that Archer and Tpol are occupied by aliens.
<PRP> eventually discovers that <PERSON>4 and <PERSON>5 are occupied by Synset('entrant.n.03').