??? ??? ????? ?????? ??????? ??? ?? ????? ?????? ????? ??? ??????? ????? ???? ??? ??? ?? ??? ????? ??? ??? ?????? ???? ?? ???? ?? ???? ????? ??? ????? ????? ????????? ??? ??? ??? ?? ????? ????? ??????. It has been customary in surveys on the Arabic literary custom to write off the period amongst 12