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 ":".
He
was
acutely
aware
of
the
risks
,
as
many
of
his
playing
colleagues
had
been
killed
,
injured
or
captured
.
He:O
was:O
acutely:O
aware:O
of:O
the:O
risks:O
,:O
as:O
many:O
of:O
his:O
playing:O
colleagues:O
had:O
been:O
killed:O
,:O
injured:O
or:O
captured:O
.:O