With no explanation, label each line with "O", "organization-other", "product-train", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart" or "building-airport" preceded by ":".
From
the
mid-1970s
,
steam
was
replaced
by
Class
91-000
diesel-electric
locomotives
on
the
SAR
's
longer
routes
,
which
were
more
powerful
.
From:O
the:O
mid-1970s:O
,:O
steam:O
was:O
replaced:O
by:O
Class:product-train
91-000:product-train
diesel-electric:O
locomotives:O
on:O
the:O
SAR:organization-other
's:O
longer:O
routes:O
,:O
which:O
were:O
more:O
powerful:O
.:O