With no explanation, label each line with "O", "organization-other", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
On
31
May
Company
A
,
1/61st
made
contact
with
a
PAVN
platoon
killing
three
.
On:O
31:O
May:O
Company:O
A:O
,:O
1/61st:O
made:O
contact:O
with:O
a:O
PAVN:organization-other
platoon:O
killing:O
three:O
.:O