With no explanation, label each line with "O", "person-athlete", "event-sportsevent", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart" or "building-airport" preceded by ":".
He
challenged
WBC
Featherweight
Title
holder
Erik
Morales
on
July
28
,
2001
,
but
lost
a
unanimous
decision
.
He:O
challenged:O
WBC:event-sportsevent
Featherweight:O
Title:O
holder:O
Erik:person-athlete
Morales:person-athlete
on:O
July:O
28:O
,:O
2001:O
,:O
but:O
lost:O
a:O
unanimous:O
decision:O
.:O