With no explanation, label each line with "O", "other-astronomything", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
Because
perchlorate
would
have
broken
down
any
Martian
organics
,
the
question
of
whether
or
not
Viking
found
life
is
still
wide
open
.
Because:O
perchlorate:O
would:O
have:O
broken:O
down:O
any:O
Martian:other-astronomything
organics:O
,:O
the:O
question:O
of:O
whether:O
or:O
not:O
Viking:other-astronomything
found:O
life:O
is:O
still:O
wide:O
open:O
.:O