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 ":".
The
embryo
secretes
human
chorionic
gonadotropin
(
hCG
)
,
which
downregulates
anti-adhesion
factor
,
MUC-1
,
located
on
the
uterine
epithelium
at
the
site
of
invasion
.
The:O
embryo:O
secretes:O
human:other-biologything
chorionic:other-biologything
gonadotropin:other-biologything
(:O
hCG:other-biologything
):O
,:O
which:O
downregulates:O
anti-adhesion:O
factor:O
,:O
MUC-1:other-biologything
,:O
located:O
on:O
the:O
uterine:O
epithelium:O
at:O
the:O
site:O
of:O
invasion:O
.:O