With no explanation, label each line with "O", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport", "building-hospital" or "building-hotel" preceded by ":".
By
1948
most
of
the
railway
system
was
operable
,
some
larger
bridges
needing
more
time
to
be
rebuilt
.
By:O
1948:O
most:O
of:O
the:O
railway:O
system:O
was:O
operable:O
,:O
some:O
larger:O
bridges:O
needing:O
more:O
time:O
to:O
be:O
rebuilt:O
.:O