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 ":".
One
aircraft
was
lost
on
mission
during
this
period
.
One:O
aircraft:O
was:O
lost:O
on:O
mission:O
during:O
this:O
period:O
.:O