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 ":".
Four
branch
libraries
were
opened
in
June
1912
.
Four:O
branch:O
libraries:O
were:O
opened:O
in:O
June:O
1912:O
.:O