 They can also alter the speed of the Tala "(Pratilomam)" and keep the speed of the "Sahityam" constant.Once this is completed then they would sing the "Pallavi" in different "Nadais" (Mostly "Tisra" Nadai meaning each beat now carries 3 units) i.e.keeping the words and the length of the pallavi constant but changing the "nadai" of the "thalam."