With no explanation, label each line with "product-other", "location-GPE", "O", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart" or "building-airport" preceded by ":".
Although
designated
a
medium
bombardment
unit
,
it
was
equipped
with
Douglas
O-46
and
North
American
O-47
single-engine
observation
aircraft
.
Although:O
designated:O
a:O
medium:O
bombardment:O
unit:O
,:O
it:O
was:O
equipped:O
with:O
Douglas:product-other
O-46:product-other
and:O
North:O
American:location-GPE
O-47:product-other
single-engine:O
observation:O
aircraft:O
.:O