With no explanation, label each line with "O", "person-director", "person-actor", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart" or "building-airport" preceded by ":".
The
pair
had
previously
collaborated
in
Madhavan
's
films
under
the
direction
of
Mani
Ratnam
,
where
Sudha
had
been
an
associate
director
.
The:O
pair:O
had:O
previously:O
collaborated:O
in:O
Madhavan:person-actor
's:O
films:O
under:O
the:O
direction:O
of:O
Mani:person-director
Ratnam:person-director
,:O
where:O
Sudha:person-director
had:O
been:O
an:O
associate:O
director:O
.:O