['they', 'distinguish', 'EmptyParameter', 'sleep', 'between']
['<PRP>', 'distinguish-23.5-1', 'EmptyParameter', "Synset('state.n.02')", 'between']
They were unable to distinguish between sleep and sedation.
<PRP> were Synset('unable.a.01') to distinguish between Synset('state.n.02') and Synset('medication.n.02').