With no explanation, label each line with "O", "organization-other", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
Each
year
,
it
draws
thousands
of
competitors
,
from
serious
international
athletes
and
Olympic
medallists
to
purely
recreational
swimmers
.
Each:O
year:O
,:O
it:O
draws:O
thousands:O
of:O
competitors:O
,:O
from:O
serious:O
international:O
athletes:O
and:O
Olympic:organization-other
medallists:O
to:O
purely:O
recreational:O
swimmers:O
.:O