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 ":".
On
Sundays
the
first
southbound
train
leaves
at
about
9:30
am
and
the
first
northbound
train
leaves
at
about
10:30
am
.
On:O
Sundays:O
the:O
first:O
southbound:O
train:O
leaves:O
at:O
about:O
9:30:O
am:O
and:O
the:O
first:O
northbound:O
train:O
leaves:O
at:O
about:O
10:30:O
am:O
.:O