['they', 'make', 'discovery', 'EmptyParameter', 'EmptyParameter']
['<PRP>', 'act-114', "Synset('speech_act.n.01')", 'EmptyParameter', 'EmptyParameter']
They make a startling discovery on the planet's surface.
<PRP> make a startling Synset('speech_act.n.01') on the planet's Synset('feature.n.01').