['they', 'arrive', 'EmptyParameter', 'field', 'at']
['<PRP>', 'escape-51.1-1', 'EmptyParameter', "Synset('percept.n.01')", 'at']
They have arrived at the debris field.
<PRP> have arrived at the Synset('waste.n.01') Synset('percept.n.01').