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
is
thought
to
be
due
to
abnormal
development
of
the
heart
.
This:O
is:O
thought:O
to:O
be:O
due:O
to:O
abnormal:O
development:O
of:O
the:O
heart:O
.:O