With no explanation, label each line with "product-other", "product-airplane", "O", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart" or "building-airport" preceded by ":".
The
first
prototype
,
known
as
the
IL-400
,
was
designed
around
the
Liberty
L-12
piston
engine
.
The:O
first:O
prototype:O
,:O
known:O
as:O
the:O
IL-400:product-airplane
,:O
was:O
designed:O
around:O
the:O
Liberty:product-other
L-12:product-other
piston:product-other
engine:product-other
.:O