With no explanation, label each line with "O", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport", "building-hospital" or "building-hotel" preceded by ":".
However
,
if
the
auction
is
held
``
without
reserve
''
then
the
auctioneer
is
obliged
to
sell
to
the
highest
bidder
.
However:O
,:O
if:O
the:O
auction:O
is:O
held:O
``:O
without:O
reserve:O
'':O
then:O
the:O
auctioneer:O
is:O
obliged:O
to:O
sell:O
to:O
the:O
highest:O
bidder:O
.:O