With no explanation, label each line with "O", "product-weapon", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
By
1971
,
the
larger
T-54
medium
tanks
were
fielded
,
proving
themselves
susceptible
to
the
M-72
LAW
rocket
,
ARVN
M41
Walker
Bulldog
light
tanks
,
as
well
as
the
larger
M48A3
Pattons
.
By:O
1971:O
,:O
the:O
larger:O
T-54:product-weapon
medium:O
tanks:O
were:O
fielded:O
,:O
proving:O
themselves:O
susceptible:O
to:O
the:O
M-72:product-weapon
LAW:product-weapon
rocket:O
,:O
ARVN:product-weapon
M41:product-weapon
Walker:product-weapon
Bulldog:product-weapon
light:O
tanks:O
,:O
as:O
well:O
as:O
the:O
larger:O
M48A3:product-weapon
Pattons:product-weapon
.:O