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 ":".
The
base
was
at
RAF
Changi
,
Singapore
,
from
April
1946
until
October
1967
.
The:O
base:O
was:O
at:O
RAF:location-other
Changi:location-other
,:O
Singapore:location-GPE
,:O
from:O
April:O
1946:O
until:O
October:O
1967:O
.:O