With no explanation, label each line with "O", "organization-politicalparty", "person-politician", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart" or "building-airport" preceded by ":".
Pol
Pot
had
been
CPK
general
secretary
since
February
1963
.
Pol:person-politician
Pot:person-politician
had:O
been:O
CPK:organization-politicalparty
general:O
secretary:O
since:O
February:O
1963:O
.:O