The relation between theme vowels and root suppletion

Abstract This chapter discusses root suppletion and theme vowels in Romance. When a verb has both an all-purpose root and a different root that only occurs in a particular tense, the special root is incompatible with the general theme vowel that the associated all-purpose root comes with. The author illustrates this with Italian passato remoto paradigms and Portuguese pretérito paradigms, and argues that the relationbetween theme vowels and root suppletion is a direct consequence of basic assumptions of Nanosyntax: the size of the tree in the lexical entry for a root determines which theme vowel the root comes with, and two competing roots with the same conceptual content cannot be associated with the same lexical tree.