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 ":".
601
Squadron
RAF
over
Channel
with
the
loss
of
all
crews
.
601:O
Squadron:O
RAF:O
over:O
Channel:O
with:O
the:O
loss:O
of:O
all:O
crews:O
.:O