We used a cross-modal priming procedure to explore the processing of irregular and regular English verb forms in both monolinguals and bilinguals (Serbian-English, Chinese-English). Materials included irregular nested stem (drawn-DRAW), irregular change stem (ran-RUN), and regular past tense-present tense verb pairs that were either low (guided-GUIDE) or high (pushed-PUSH) in resonance, a measure of semantic richness. Overall, semantic richness of irregular verbs (nested and irregular change) and of regular verbs (high and low resonance) was matched. Native speakers of English revealed comparable facilitation across regularity and greater facilitation for nested than change stem irregulars. Like native speakers, Serbian, but not Chinese bilinguals matched for proficiency, showed facilitation due to form overlap between irregular past and present tense forms with a nested stem. Unlike native speakers, neither group showed reliable facilitation to stem change irregulars. Results demonstrate the influence of first language on inflectional processing in a second language.Keywords semantic density; language transfer; morphological facilitation; cross modal priming; regular past tense formations; irregular past tense formations; mastery of inflection in a second language There is a long-standing debate in the word recognition literature as to whether native speakers of a language process irregular (e.g., ran-run) and regular (e.g., walked-walk) verb forms by common (single) or different (dual-route) mechanisms. Those who advocate a single processing system argue that processing of all words benefits from the extent to which words that are similar in form tend to be similar in meaning (