CALL AND RESPONSE - This term is not so much of a strict "form" of African music as it is a process by which music is created. The "call" is usually a short motivic melodic fragment which is "responded to" in the "response" segment of the process.

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call and response is process
call and response uses short motivic fragment
call and response uses long elaborate answer
call and response has feature _call_
call and response has feature _response_
call and response is form of African music