This action research explored the impact of Bard-generated feedback on enhancing paragraph writing skills among 47 grade 11 students in Hanoi, using the English textbook 11: Bright textbook over half a semester. Employing a mixed-methods approach, pre- and post-tests measured writing improvements, while surveys and observations captured student perceptions. Results showed significant gains in lexical resource and grammatical accuracy, with students valuing the clear, timely feedback. Integrating Bard into writing instruction proved effective, suggesting teachers adopt AI tools to enhance learning. Future research could examine long-term effects and broader applications.