['Greth', 'challenge', 'he', 'fight', 'to']
['<PERSON>9', 'challenge', '<PRP>', "Synset('group_action.n.01')", 'to']
Greth challenges him to a fight to the death.
<PERSON>9 challenges <PRP> to a Synset('group_action.n.01') to the Synset('attribute.n.02').