With no explanation, label each line with "O", "location-other", "person-politician", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart" or "building-airport" preceded by ":".
It
was
constructed
in
1931
as
``
part
of
President
Lowell
's
plan
to
enclose
the
Yard
from
the
traffic
of
Harvard
Square
.
''
It:O
was:O
constructed:O
in:O
1931:O
as:O
``:O
part:O
of:O
President:O
Lowell:person-politician
's:O
plan:O
to:O
enclose:O
the:O
Yard:O
from:O
the:O
traffic:O
of:O
Harvard:location-other
Square:location-other
.:O
'':O