With no explanation, label each line with "O", "organization-company", "product-train", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart" or "building-airport" preceded by ":".
The
trains
were
replaced
by
Northern
line
tube
trains
on
15
May
1939
and
all
the
original
GN
&
amp
;
C
stock
was
scrapped
.
The:O
trains:O
were:O
replaced:O
by:O
Northern:organization-company
line:organization-company
tube:O
trains:O
on:O
15:O
May:O
1939:O
and:O
all:O
the:O
original:O
GN:product-train
&:product-train
amp:product-train
;:product-train
C:product-train
stock:O
was:O
scrapped:O
.:O