<b>Teaching Languages with Machines: A Systematic Review on the Effectiveness of AI in ESL Learning </b>

This systematic literature review investigates the integration of Artificial Intelligence (AI) tools in English as a Second Language (ESL) learning by evaluating their impact on language skill development and learner engagement while determining related challenges and strategies for effective implementation. The review analyzes how tools like ChatGPT, Duolingo, Grammarly, Wordtune, and Pigai are used across instructional phases such as drafting, practice, and assessment to support writing, speaking, listening, vocabulary, grammar, and reading comprehension which are drawn on 19 peer-reviewed studies published between 2021 and 2025. The findings show that AI improves learner motivation, confidence, and participation using personalized, real-time feedback and adaptive learning experiences. However, limitations such as over-reliance on AI, limited contextual understanding, technological challenges, and lack of thorough experimental designs are noted. To address these, the study recommends combining AI with teacher guidance and offering targeted training, expanding AI content for advanced learners and embedding AI literacy into curricula. The review contributes useful insights for educators, researchers, and developers who aim to maximize AI integration in ESL learning.