With no explanation, label each line with "O", "location-bodiesofwater", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
It
crosses
near
the
mouth
of
the
Chicago
River
.
It:O
crosses:O
near:O
the:O
mouth:O
of:O
the:O
Chicago:location-bodiesofwater
River:location-bodiesofwater
.:O