Here is a question about this article: Like all the Romance languages, Catalan verbal inflection is more complex than the nominal. Suffixation is omnipresent, whereas morphological alternations play a secondary role. Vowel alternances are active, as well as infixation and suppletion. However, these are not as productive as in Spanish, and are mostly restricted to irregular verbs.
What is the answer to this question: What plays a secondary part in Catalan?
morphological alternations