With no explanation, label each line with "O", "other-chemicalthing", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
Heavy
water
has
been
demonstrated
as
an
effective
moderator
for
239Pu
production
,
and
may
be
separated
from
ordinary
water
by
electrolysis
.
Heavy:O
water:O
has:O
been:O
demonstrated:O
as:O
an:O
effective:O
moderator:O
for:O
239Pu:other-chemicalthing
production:O
,:O
and:O
may:O
be:O
separated:O
from:O
ordinary:O
water:O
by:O
electrolysis:O
.:O