The integration of technologies into education has significantly expanded, resulting in the wide application of digital tools in traditional face-to-face classrooms and in distance education (DL), where digital solutions are integral to course delivery. This form of education has become prominent over the last few years, and its popularity is attributed to the flexibility it provides, making it well-suited for modern, fast-paced life. At the same time, the rapid spread of artificial intelligence (AI) and its topicality in education nowadays has been widely recognised, along with the opportunities and challenges it has brought. As a result, its application for the purposes of course content and tasks development has to be carefully considered not only in traditional but also in DL contexts. When designing courses for the digital environment, the available functions of the learning management system (LMS) Moodle, commonly used to deliver DL courses, are utilized and complemented by AI tools that are becoming an integral part of online course design. Developing an online language course is a challenging task since both language skills and vocabulary development have to be addressed. Vocabulary plays an essential role in any language course; however, its importance in a business English (BE) courses is crucial, as it is important for efficient interaction within business settings. Therefore, sufficient time and resources should be allocated for this component of a DL BE language course. Taking into consideration the popularity of AI platforms nowadays and the high demand for DL involving the use of digital solutions, the integration of AI tools in such language courses has to be considered and regarded as a way to create tasks for language skills development, including vocabulary acquisition. Consequently, the present case study investigates a Moodle-based DL BE course, delivered at the tertiary level, specifically concentrating on tasks aimed at students’ vocabulary enhancement. Therefore, the goal of the study is to ascertain the efficiency of AI tools, particularly the ChatGPT-5 platform, utilised specifically for vocabulary tasks design in a DL BE course. To pursue the stated goal, ChatGPT-5 was employed to create vocabulary-related tasks, which were further integrated into the LMS Moodle. In order to assess the efficiency of AI-assisted created tasks, a learner corpus containing students’ recorded presentations (RPs) was analysed. The analysis concentrated on detecting the extent to which the vocabulary included in AI-designed course tasks appeared in the students’ RPs. The analysis of the compiled learner corpus revealed that the AI-assisted tasks contributed to the learners’ vocabulary enhancement. Specifically, lexical items included in AI-designed tasks were detected in DL students’ RPs, submitted as a part of the DL BE course assessment system, with varying frequency levels. Ultimately, AI tools, namely ChatGPT-5, can be employed for vocabulary-oriented tasks design in DL BE courses. However, it is essential to highlight that prior to the implementation of AI-designed tasks, they have to be reviewed by course instructors. In particular, attention has to be paid to the alignment of the tasks with the course objectives, its content, and learners’ language proficiency level to ensure the value of the AI-generated activities.

Keywords: Artificial Intelligence (AI), task design, distance learning (DL), business English course, vocabulary acquisition.