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 ":".
The
presence
of
iron
was
reiterated
and
changes
in
rock
and
mineral
composition
have
been
identified
.
The:O
presence:O
of:O
iron:O
was:O
reiterated:O
and:O
changes:O
in:O
rock:O
and:O
mineral:O
composition:O
have:O
been:O
identified:O
.:O