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 ":".
At
the
time
of
their
arrival
,
many
of
the
airfield
buildings
were
still
uncompleted
.
At:O
the:O
time:O
of:O
their:O
arrival:O
,:O
many:O
of:O
the:O
airfield:O
buildings:O
were:O
still:O
uncompleted:O
.:O