Like other Romance languages, Romanian has traditionally received a Latin-inspired classification of verbs into 4 conjugational classes (or sometimes 5, where the 4th conjugation is divided between verbs with the infinitive ending in i andî, respectively) based on the ending of their infinitival form alone (Costanzo, 2011).
this infinitive-based classification has often been found inadequate due to the many conjugational patterns that have been found in each class and to its inability to account for the behavior of partially irregular verbs (those whose stem has a smaller number of allomorphs than the completely irregular such as "a fi") during their conjugation.