With no explanation, label each line with "O", "organization-company", "person-other", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart" or "building-airport" preceded by ":".
Northern
Rail
's
successor
Arriva
Rail
North
at
one
point
operated
the
largest
fleet
of
Class
153
units
.
Northern:organization-company
Rail:organization-company
's:O
successor:O
Arriva:person-other
Rail:person-other
North:person-other
at:O
one:O
point:O
operated:O
the:O
largest:O
fleet:O
of:O
Class:O
153:O
units:O
.:O