With no explanation, label each line with "O", "other-biologything", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
It
catalyzes
the
reduction
of
uracil
and
thymine
.
It:O
catalyzes:O
the:O
reduction:O
of:O
uracil:other-biologything
and:O
thymine:other-biologything
.:O