With no explanation, label each line with "O", "organization-sportsleague", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
Since
April
2011
,
Lega
Serie
B
has
joined
the
European
Professional
Football
Leagues
association
.
Since:O
April:O
2011:O
,:O
Lega:organization-sportsleague
Serie:organization-sportsleague
B:organization-sportsleague
has:O
joined:O
the:O
European:organization-sportsleague
Professional:organization-sportsleague
Football:organization-sportsleague
Leagues:organization-sportsleague
association:O
.:O