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 ":".
Of
the
31
aboard
,
23
were
killed
,
including
all
three
crew
members
,
and
20
of
the
28
passengers
.
Of:O
the:O
31:O
aboard:O
,:O
23:O
were:O
killed:O
,:O
including:O
all:O
three:O
crew:O
members:O
,:O
and:O
20:O
of:O
the:O
28:O
passengers:O
.:O