(a small piece of paper that is supposed to be removed when a hole is punched in a card or paper tape)
(a lake in north central Africa; fed by the Shari river)
(a landlocked desert republic in north-central Africa; was under French control until 1960)
(a family of Afroasiatic tonal languages (mostly two tones) spoken in the regions west and south of Lake Chad in north central Africa)