With no explanation, label each line with "O", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport", "building-hospital" or "building-hotel" preceded by ":".
It
is
maintained
at
three
levels
:
national
,
state
and
local
.
It:O
is:O
maintained:O
at:O
three:O
levels:O
::O
national:O
,:O
state:O
and:O
local:O
.:O