The basis of Sanskrit morphology is the root, states Jamison, "a morpheme bearing lexical meaning". The verbal and nominal stems of Sanskrit words are derived from this root through the phonological vowel-gradation processes, the addition of affixes, verbal and nominal stems. It then adds an ending to establish the grammatical and syntactic identity of the stem. According to Jamison, the "three major formal elements of the morphology are (i) root, (ii) affix, and (iii) ending; and they are roughly responsible for (i) lexical meaning, (ii) derivation, and (iii) inflection respectively".