With no explanation, label each line with "O", "event-election", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
The
debates
were
the
latest
in
a
series
of
presidential
debates
first
held
during
the
1960
presidential
election
and
held
every
four
years
since
the
1976
election
.
The:O
debates:O
were:O
the:O
latest:O
in:O
a:O
series:O
of:O
presidential:O
debates:O
first:O
held:O
during:O
the:O
1960:O
presidential:event-election
election:event-election
and:O
held:O
every:O
four:O
years:O
since:O
the:O
1976:O
election:O
.:O