With no explanation, label each line with "O", "organization-company", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
Its
aircraft
and
routes
were
taken
over
by
Dan-Air
in
1961
.
Its:O
aircraft:O
and:O
routes:O
were:O
taken:O
over:O
by:O
Dan-Air:organization-company
in:O
1961:O
.:O