The emergence of English as a lingua franca (ELF) has focused scholarly attention on non-native speakers' use of communication strategies (CSs) in international communication, which places emphasis on ensuring mutual understanding. With reference to previous ELF pragmatics research, this study examined the extent to which L2 learners' use of CSs reflects that in ELF interactions in a group interaction task in Hong Kong's high-stakes public examination. Our analysis of the students' CSs use was accompanied by semi-structured focus group interviews, allowing them to reflect on their own performance and prior English learning/use experience. The findings revealed an unnatural discursive pattern resulting from the assessment task design, although some CSs were found that have been identified in previous ELF studies. Students with higher academic attainment were more capable of using some higher-level CSs and diversifying their language forms, but this was mainly because of their higher English proficiency level/motivation, exposure to English and awareness of effective communication rather than their prior English-learning experience in the classroom. The paper concludes by offering suggestions for the design of communicative tasks and language learning/teaching practices to address the misalignment between L2 students' pragmatic production and naturalistic ELF situations. Copyright © 2021 Elsevier.