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 ":".
A
single
event
,
however
,
can
affect
a
relatively
large
number
of
people
.
A:O
single:O
event:O
,:O
however:O
,:O
can:O
affect:O
a:O
relatively:O
large:O
number:O
of:O
people:O
.:O