['parent', 'do', 'EmptyParameter', 'EmptyParameter', 'EmptyParameter']
["Synset('progenitor.n.01')", 'act-114-1', 'EmptyParameter', 'EmptyParameter', 'EmptyParameter']
His parents, who were crewmembers, did not.
<PRP> parents, who were crewmembers, did not.