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 ":".
Accounts
differ
as
to
the
specifics
of
what
happened
on
April
11
.
Accounts:O
differ:O
as:O
to:O
the:O
specifics:O
of:O
what:O
happened:O
on:O
April:O
11:O
.:O