With no explanation, label each line with "O", "event-protest", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
However
,
in
1979
,
the
Islamic
revolution
happened
and
his
plans
had
to
be
postponed
.
However:O
,:O
in:O
1979:O
,:O
the:O
Islamic:event-protest
revolution:event-protest
happened:O
and:O
his:O
plans:O
had:O
to:O
be:O
postponed:O
.:O