With no explanation, label each line with "O", "product-weapon", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
The
Polsten
was
used
as
a
substitute
for
the
Oerlikon
in
the
same
roles
,
one
of
which
was
as
an
airborne
unit
anti-aircraft
gun
,
used
in
Operation
Market
Garden
.
The:O
Polsten:product-weapon
was:O
used:O
as:O
a:O
substitute:O
for:O
the:O
Oerlikon:product-weapon
in:O
the:O
same:O
roles:O
,:O
one:O
of:O
which:O
was:O
as:O
an:O
airborne:O
unit:O
anti-aircraft:O
gun:O
,:O
used:O
in:O
Operation:O
Market:O
Garden:O
.:O