With no explanation, label each line with "O", "building-hospital", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hotel" preceded by ":".
Then
he
did
residency
in
ophthalmology
at
Farabi
Eye
Hospital
from
1979
to
1982
.
Then:O
he:O
did:O
residency:O
in:O
ophthalmology:O
at:O
Farabi:building-hospital
Eye:building-hospital
Hospital:building-hospital
from:O
1979:O
to:O
1982:O
.:O