['that', 'control', 'they', 'EmptyParameter', 'EmptyParameter'] ['he', 'learn', 'control', 'EmptyParameter', 'EmptyParameter']
['that', 'enforce-63', '<PRP>', 'EmptyParameter', 'EmptyParameter'] ['<PRP>', 'learn-14-1', 'enforce-63', 'EmptyParameter', 'EmptyParameter']
His emotions can be a powerful tool, but that he must learn to control them.
<PRP> Synset('state.n.02') can be a Synset('powerful.a.01') tool, but that <PRP> must learn to control <PRP>.