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 ":".
This
truss
has
been
used
in
the
construction
of
a
stadium
,
with
the
upper
chords
of
parallel
trusses
supporting
a
roof
that
may
be
rolled
back
.
This:O
truss:O
has:O
been:O
used:O
in:O
the:O
construction:O
of:O
a:O
stadium:O
,:O
with:O
the:O
upper:O
chords:O
of:O
parallel:O
trusses:O
supporting:O
a:O
roof:O
that:O
may:O
be:O
rolled:O
back:O
.:O