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 ":".
It
opened
to
the
general
public
in
1974
as
part
of
the
former
roaring
20
's
expansion
area
.
It:O
opened:O
to:O
the:O
general:O
public:O
in:O
1974:O
as:O
part:O
of:O
the:O
former:O
roaring:O
20:O
's:O
expansion:O
area:O
.:O