With no explanation, label each line with "O", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport", "building-hospital" or "building-hotel" preceded by ":".
Enemy
spacecraft
attack
the
vessel
in
groups
of
three
,
and
the
player
must
aim
a
set
of
crosshairs
and
shoot
the
enemies
before
they
slip
past
the
player
's
cannons
.
Enemy:O
spacecraft:O
attack:O
the:O
vessel:O
in:O
groups:O
of:O
three:O
,:O
and:O
the:O
player:O
must:O
aim:O
a:O
set:O
of:O
crosshairs:O
and:O
shoot:O
the:O
enemies:O
before:O
they:O
slip:O
past:O
the:O
player:O
's:O
cannons:O
.:O