With no explanation, label each line with "location-GPE", "organization-other", "event-attack/battle/war/militaryconflict", "O", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting" or "art-writtenart" preceded by ":".
Fifth
Army
was
engaged
in
the
Battle
of
the
Ancre
Heights
Ancre
Heights
,
the
last
phase
of
that
summer
's
Somme
Offensive
.
Fifth:organization-other
Army:organization-other
was:O
engaged:O
in:O
the:O
Battle:event-attack/battle/war/militaryconflict
of:event-attack/battle/war/militaryconflict
the:event-attack/battle/war/militaryconflict
Ancre:event-attack/battle/war/militaryconflict
Heights:event-attack/battle/war/militaryconflict
Ancre:location-GPE
Heights:O
,:O
the:O
last:O
phase:O
of:O
that:O
summer:O
's:O
Somme:event-attack/battle/war/militaryconflict
Offensive:event-attack/battle/war/militaryconflict
.:O