With no explanation, label each line with "O", "other-astronomything", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
The
presence
of
an
ordinary
star
in
such
a
system
provides
an
opportunity
for
studying
the
central
object
and
to
determine
if
it
might
be
a
black
hole
.
The:O
presence:O
of:O
an:O
ordinary:O
star:O
in:O
such:O
a:O
system:O
provides:O
an:O
opportunity:O
for:O
studying:O
the:O
central:O
object:O
and:O
to:O
determine:O
if:O
it:O
might:O
be:O
a:O
black:other-astronomything
hole:other-astronomything
.:O