With no explanation, label each line with "O", "event-disaster", "person-other", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart" or "building-airport" preceded by ":".
Two
days
later
,
Dr
.
Wilmer
Krusen
concluded
that
the
Spanish
flu
was
now
present
in
the
civilian
population
.
Two:O
days:O
later:O
,:O
Dr:O
.:O
Wilmer:person-other
Krusen:person-other
concluded:O
that:O
the:event-disaster
Spanish:event-disaster
flu:event-disaster
was:O
now:O
present:O
in:O
the:O
civilian:O
population:O
.:O