With no explanation, label each line with "organization-showorganization", "O", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
They
would
often
work
with
Yr
Anhrefn
,
either
supporting
them
in
their
concerts
or
doing
the
reverse
,
when
Y
Cyrff
were
booked
as
the
lead
act
.
They:O
would:O
often:O
work:O
with:O
Yr:organization-showorganization
Anhrefn:organization-showorganization
,:O
either:O
supporting:O
them:O
in:O
their:O
concerts:O
or:O
doing:O
the:O
reverse:O
,:O
when:O
Y:organization-showorganization
Cyrff:organization-showorganization
were:O
booked:O
as:O
the:O
lead:O
act:O
.:O