With no explanation, label each line with "O", "event-sportsevent", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
The
2012
MercedesCup
was
a
men
's
tennis
tournament
played
on
outdoor
clay
courts
.
The:O
2012:event-sportsevent
MercedesCup:event-sportsevent
was:O
a:O
men:O
's:O
tennis:O
tournament:O
played:O
on:O
outdoor:O
clay:O
courts:O
.:O