With no explanation, label each line with "location-GPE", "O", "person-other", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart" or "building-airport" preceded by ":".
In
early
1872
he
traveled
to
California
to
visit
his
ailing
friend
Letterman
.
In:O
early:O
1872:O
he:O
traveled:O
to:O
California:location-GPE
to:O
visit:O
his:O
ailing:O
friend:O
Letterman:person-other
.:O