With no explanation, label each line with "O", "organization-company", "organization-education", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart" or "building-airport" preceded by ":".
After
graduating
from
Barnard
College
she
joined
American
Telephone
and
Telegraph
Company
(
AT
&
amp
;
T
)
where
she
worked
as
a
switchboards
instructor
.
After:O
graduating:O
from:O
Barnard:organization-education
College:organization-education
she:O
joined:O
American:organization-company
Telephone:organization-company
and:organization-company
Telegraph:organization-company
Company:organization-company
(:O
AT:organization-company
&:organization-company
amp:organization-company
;:organization-company
T:organization-company
):O
where:O
she:O
worked:O
as:O
a:O
switchboards:O
instructor:O
.:O