With no explanation, label each line with "product-airplane", "O", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
However
,
the
AV.29
,
in
both
forms
,
remained
a
paper
project
only
.
However:O
,:O
the:O
AV.29:product-airplane
,:O
in:O
both:O
forms:O
,:O
remained:O
a:O
paper:O
project:O
only:O
.:O