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 ":".
When
the
United
States
began
flying
bombing
missions
against
Germany
,
it
reinforced
these
efforts
and
controversial
firebombings
were
carried
out
against
Hamburg
(
1943
)
,
Dresden
(
1945
)
,
and
other
German
cities
.
When:O
the:O
United:location-GPE
States:location-GPE
began:O
flying:O
bombing:O
missions:O
against:O
Germany:location-GPE
,:O
it:O
reinforced:O
these:O
efforts:O
and:O
controversial:O
firebombings:O
were:O
carried:O
out:O
against:O
Hamburg:location-GPE
(:O
1943:O
):O
,:O
Dresden:location-GPE
(:O
1945:O
):O
,:O
and:O
other:O
German:location-GPE
cities:O
.:O