['he', 'discover', 'EmptyParameter', 'EmptyParameter', 'EmptyParameter']
['<PRP>', 'discover-84', 'EmptyParameter', 'EmptyParameter', 'EmptyParameter']
He discovered about that could slow down the aging process.
<PRP> discovered about that could slow down the Synset('process.n.06') Synset('psychological_feature.n.01').