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 ":".
Between
1951
and
1955
,
over
a
hundred
of
its
enterprises
were
shut
down
or
merged
.
Between:O
1951:O
and:O
1955:O
,:O
over:O
a:O
hundred:O
of:O
its:O
enterprises:O
were:O
shut:O
down:O
or:O
merged:O
.:O