With no explanation, label each line with "location-GPE", "O", "event-attack/battle/war/militaryconflict", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart" or "building-airport" preceded by ":".
Because
of
the
economic
crisis
in
Germany
after
the
First
World
War
,
there
was
no
gold
available
to
back
the
currency
.
Because:O
of:O
the:O
economic:O
crisis:O
in:O
Germany:location-GPE
after:O
the:O
First:event-attack/battle/war/militaryconflict
World:event-attack/battle/war/militaryconflict
War:event-attack/battle/war/militaryconflict
,:O
there:O
was:O
no:O
gold:O
available:O
to:O
back:O
the:O
currency:O
.:O