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 ":".
BCF
is
commercially
synthesized
in
a
two-step
process
from
chloroform
.
BCF:other-chemicalthing
is:O
commercially:O
synthesized:O
in:O
a:O
two-step:O
process:O
from:O
chloroform:other-chemicalthing
.:O