With no explanation, label each line with "person-athlete", "event-sportsevent", "O", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart" or "building-airport" preceded by ":".
Boelen
's
daughter
Femke
is
also
an
Olympic
rower
.
Boelen:person-athlete
's:O
daughter:O
Femke:person-athlete
is:O
also:O
an:O
Olympic:event-sportsevent
rower:O
.:O