Isitshalo esinamaqabunga uhlobo lwesitshalo esilahla amaqabunga aso njalo ngonyaka noma phakathi nesizini ethile, ngokuvamile ekwindla noma ekwindla. Izitshalo ezivuthulukayo zihlanganisa izihlahla, izihlahlana, nezinye izitshalo ezinamakhambi, futhi zibonakala ngokukwazi ukuzivumelanisa nezimo zemvelo ezishintshayo, njengezinga lokushisa nokutholakala kokukhanya, ngokulahlekelwa amaqabunga azo. Ngesikhathi sokukhula, izitshalo ezivuthulukayo zikhiqiza amaqabunga amasha nokunye ukukhula, kodwa ekwindla, amaqabunga ashintsha umbala bese ewa, okushiya isitshalo sithule kuze kube inkathi elandelayo yokukhula.