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 ":".
It
was
then
``
the
largest
flying
military
aviation
unit
in
the
world
''
.
It:O
was:O
then:O
``:O
the:O
largest:O
flying:O
military:O
aviation:O
unit:O
in:O
the:O
world:O
'':O
.:O