With no explanation, label each line with "product-other", "O", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
The
Mamba
-powered
prototype
was
later
refitted
with
Alvis
Leonides
Major
radial
engines
and
used
to
assist
development
of
the
projected
Handley
Page
Herald
.
The:O
Mamba:product-other
-powered:O
prototype:O
was:O
later:O
refitted:O
with:O
Alvis:product-other
Leonides:product-other
Major:product-other
radial:O
engines:O
and:O
used:O
to:O
assist:O
development:O
of:O
the:O
projected:O
Handley:product-other
Page:product-other
Herald:product-other
.:O