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 ":".
Isolation
of
the
kernel
without
the
thin
but
tough
shell
(
or
``
testa
''
)
is
difficult
.
Isolation:O
of:O
the:O
kernel:O
without:O
the:O
thin:O
but:O
tough:O
shell:O
(:O
or:O
``:O
testa:O
'':O
):O
is:O
difficult:O
.:O