With no explanation, label each line with "O", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport", "building-hospital" or "building-hotel" preceded by ":".
Most
parts
of
city
centre
inside
the
former
walls
are
pedestrian
areas
.
Most:O
parts:O
of:O
city:O
centre:O
inside:O
the:O
former:O
walls:O
are:O
pedestrian:O
areas:O
.:O