With no explanation, label each line with "O", "location-bodiesofwater", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
The
Clutha
River
is
the
swiftest
river
(
per
volume
)
in
the
southern
hemisphere
.
The:O
Clutha:location-bodiesofwater
River:location-bodiesofwater
is:O
the:O
swiftest:O
river:O
(:O
per:O
volume:O
):O
in:O
the:O
southern:O
hemisphere:O
.:O