With no explanation, label each line with "location-GPE", "O", "event-sportsevent", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart" or "building-airport" preceded by ":".
The
1979
ATP
Buenos
Aires
was
a
men
's
Grand
Prix
tennis
circuit
tournament
held
in
Buenos
Aires
,
Argentina
that
was
played
on
outdoor
clay
courts
.
The:O
1979:O
ATP:event-sportsevent
Buenos:event-sportsevent
Aires:event-sportsevent
was:O
a:O
men:O
's:O
Grand:event-sportsevent
Prix:event-sportsevent
tennis:O
circuit:O
tournament:O
held:O
in:O
Buenos:location-GPE
Aires:location-GPE
,:O
Argentina:location-GPE
that:O
was:O
played:O
on:O
outdoor:O
clay:O
courts:O
.:O