With no explanation, label each line with "location-GPE", "O", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
The
ships
were
scuttled
there
in
the
11th
century
to
block
a
navigation
channel
and
thus
protect
[
[
Roskilde
]
]
,
then
the
Danish
capital
,
from
seaborne
assault
.
The:O
ships:O
were:O
scuttled:O
there:O
in:O
the:O
11th:O
century:O
to:O
block:O
a:O
navigation:O
channel:O
and:O
thus:O
protect:O
[:O
[:O
Roskilde:location-GPE
]:O
]:O
,:O
then:O
the:O
Danish:location-GPE
capital:O
,:O
from:O
seaborne:O
assault:O
.:O