With no explanation, label each line with "product-airplane", "O", "organization-company", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart" or "building-airport" preceded by ":".
Their
civilian
model
would
be
dubbed
a
DC-7
by
Douglas
(
Model
415A
)
and
the
'
Clipper
Type
9
'
by
Pan
American
.
Their:O
civilian:O
model:O
would:O
be:O
dubbed:O
a:O
DC-7:product-airplane
by:product-airplane
Douglas:product-airplane
(:O
Model:product-airplane
415A:product-airplane
):O
and:O
the:O
':O
Clipper:product-airplane
Type:product-airplane
9:product-airplane
':O
by:O
Pan:organization-company
American:organization-company
.:O