With no explanation, label each line with "location-GPE", "O", "organization-religion", "event-attack/battle/war/militaryconflict", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting" or "art-writtenart" preceded by ":".
The
Serbian
Revolution
ultimately
became
a
symbol
of
the
nation-building
process
in
the
Balkans
,
provoking
peasant
unrest
among
the
Christians
in
both
Greece
and
Bulgaria
.
The:O
Serbian:event-attack/battle/war/militaryconflict
Revolution:event-attack/battle/war/militaryconflict
ultimately:O
became:O
a:O
symbol:O
of:O
the:O
nation-building:O
process:O
in:O
the:O
Balkans:location-GPE
,:O
provoking:O
peasant:O
unrest:O
among:O
the:O
Christians:organization-religion
in:O
both:O
Greece:location-GPE
and:O
Bulgaria:location-GPE
.:O