['figure', 'watch', 'they', 'EmptyParameter', 'EmptyParameter']
["Synset('device.n.02')", 'search-35.2', '<PRP>', 'EmptyParameter', 'EmptyParameter']
A mysterious figure watches them from hiding without their knowledge.
a mysterious Synset('device.n.02') watches <PRP> from hiding without <PRP> Synset('abstraction.n.06').