With no explanation, label each line with "location-GPE", "O", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
Chojnice
was
an
important
center
of
cloth
production
in
Poland
.
Chojnice:location-GPE
was:O
an:O
important:O
center:O
of:O
cloth:O
production:O
in:O
Poland:location-GPE
.:O