With no explanation, label each line with "O", "event-attack/battle/war/militaryconflict", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
This
led
to
a
climax
in
the
bloody
Battle
of
Berlin
.
This:O
led:O
to:O
a:O
climax:O
in:O
the:O
bloody:O
Battle:event-attack/battle/war/militaryconflict
of:event-attack/battle/war/militaryconflict
Berlin:event-attack/battle/war/militaryconflict
.:O