With no explanation, label each line with "location-GPE", "O", "location-other", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart" or "building-airport" preceded by ":".
It
was
only
because
of
a
delay
in
Rio
that
he
was
unable
to
reach
Friedrichshafen
to
join
the
last
flight
of
the
``
Hindenburg
``
.
It:O
was:O
only:O
because:O
of:O
a:O
delay:O
in:O
Rio:location-GPE
that:O
he:O
was:O
unable:O
to:O
reach:O
Friedrichshafen:location-other
to:O
join:O
the:O
last:O
flight:O
of:O
the:O
``:O
Hindenburg:location-other
``:O
.:O