With no explanation, label each line with "O", "product-weapon", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
The
crude
and
cheap
Sten
was
a
favourite
.
The:O
crude:O
and:O
cheap:O
Sten:product-weapon
was:O
a:O
favourite:O
.:O