With no explanation, label each line with "O", "organization-company", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
Though
Sega
looked
at
options
to
bring
the
service
to
PCs
,
it
had
been
discontinued
by
July
31
,
1998
.
Though:O
Sega:organization-company
looked:O
at:O
options:O
to:O
bring:O
the:O
service:O
to:O
PCs:O
,:O
it:O
had:O
been:O
discontinued:O
by:O
July:O
31:O
,:O
1998:O
.:O