With no explanation, label each line with "location-GPE", "person-athlete", "O", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart" or "building-airport" preceded by ":".
William
Ford
(
born
December
15
,
1986
)
is
an
American
football
running
back
who
is
currently
a
free
agent
.
William:person-athlete
Ford:person-athlete
(:O
born:O
December:O
15:O
,:O
1986:O
):O
is:O
an:O
American:location-GPE
football:O
running:O
back:O
who:O
is:O
currently:O
a:O
free:O
agent:O
.:O