Abstract
This research examines the impact of the age of second language acquisition (AoA) on grammatical accuracy in Russian-English bilinguals, specifically addressing the distinction between Past Simple and Present Perfect tenses. These tenses present unique challenges for Russian speakers, as Russian employs a single past tense form, leading to frequent L1 transfer errors in English. Through a mixed-methods approach including a comprehensive literature review, participant background questionnaires, and grammaticality judgment tests the study identifies gaps in existing research on AoA effects in Russian-English bilingualism and proposes new experimental directions. Administered via the Edvibe platform, the experiment involved 13 participants (6 early bilinguals: AoA <10 years; 7 late bilinguals: AoA >10 years) completing a tailored course, Blogs Unlocked: Past and Perfect Tenses, with pre-, mid-, and post-tests. Results revealed that while early and late bilinguals did not significantly differ in final grammatical accuracy (p = 0.102), late bilinguals demonstrated statistically greater improvement between pre- and post-tests (p < 0.001 vs. p = 0.042 for early bilinguals), suggesting AoA correlates with the rate of grammatical precision enhancement. This underscores the complexity of bilingual language processing, with implications for pedagogical strategies targeting specific grammatical challenges in L2 learners. The study contributes to psycholinguistic, sociolinguistic, and neurolinguistic discourse on bilingualism, advocating for further investigation into factors like language exposure and cognitive abilities. This research will be of particular interest to educators and curriculum designers developing grammar instruction for Russian-speaking learners of English.