With no explanation, label each line with "location-GPE", "O", "person-politician", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart" or "building-airport" preceded by ":".
In
March
of
that
year
,
King
Gustav
II
Adolf
of
Sweden
and
Christian
IV
met
at
the
castle
.
In:O
March:O
of:O
that:O
year:O
,:O
King:O
Gustav:person-politician
II:person-politician
Adolf:person-politician
of:O
Sweden:location-GPE
and:O
Christian:person-politician
IV:person-politician
met:O
at:O
the:O
castle:O
.:O