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 ":".
Efforts
to
find
a
suitable
replacement
for
Halon
1301
have
not
produced
a
widely
accepted
replacement
.
Efforts:O
to:O
find:O
a:O
suitable:O
replacement:O
for:O
Halon:other-chemicalthing
1301:other-chemicalthing
have:O
not:O
produced:O
a:O
widely:O
accepted:O
replacement:O
.:O