With no explanation, label each line with "O", "organization-other", "person-other", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart" or "building-airport" preceded by ":".
The
first
western
explorers
to
discover
the
col
were
George
Mallory
and
Guy
Bullock
on
the
1921
British
Mount
Everest
reconnaissance
expedition
although
it
was
only
Bullock
who
actually
reached
it
.
The:O
first:O
western:O
explorers:O
to:O
discover:O
the:O
col:O
were:O
George:person-other
Mallory:person-other
and:O
Guy:person-other
Bullock:person-other
on:O
the:O
1921:O
British:organization-other
Mount:organization-other
Everest:organization-other
reconnaissance:O
expedition:O
although:O
it:O
was:O
only:O
Bullock:person-other
who:O
actually:O
reached:O
it:O
.:O