With no explanation, label each line with "O", "location-park", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
Canyon
de
Chelly
National
Monument
(
)
was
established
on
April
1
,
1931
,
as
a
unit
of
the
National
Park
Service
.
Canyon:location-park
de:location-park
Chelly:location-park
National:location-park
Monument:location-park
(:O
):O
was:O
established:O
on:O
April:O
1:O
,:O
1931:O
,:O
as:O
a:O
unit:O
of:O
the:O
National:location-park
Park:location-park
Service:location-park
.:O