With no explanation, label each line with "location-GPE", "O", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
During
the
final
days
of
the
Siege
of
Petersburg
in
1865
,
Wilcox
's
last-ditch
stand
on
April
2
at
Fort
Gregg
helped
delay
the
Union
forces
long
enough
for
Longstreet
to
maneuver
into
position
to
cover
the
army
's
retreat
to
the
west
.
During:O
the:O
final:O
days:O
of:O
the:O
Siege:O
of:O
Petersburg:location-GPE
in:O
1865:O
,:O
Wilcox:O
's:O
last-ditch:O
stand:O
on:O
April:O
2:O
at:O
Fort:location-GPE
Gregg:location-GPE
helped:O
delay:O
the:O
Union:O
forces:O
long:O
enough:O
for:O
Longstreet:location-GPE
to:O
maneuver:O
into:O
position:O
to:O
cover:O
the:O
army:O
's:O
retreat:O
to:O
the:O
west:O
.:O