# Educational AI Chatbots for Content and Language Integrated Learning
## 2 Preliminaries and Related Work  
Conversational AI refers to AI techniques (e.g., natural language processing, machine learning, knowledge graphs) for engineering intelligent software agents that can be engaged in natural language conversations with humans or other agents. It includes software, such as voice assistants and chatbots. The first generation of this technology focused on short task-oriented dialogue [2], such as music playback (e.g., \"Alexa, play music\") or information retrieval (e.g., \"Cortana, what is the weather today in Athens?\"). The current challenge in this area is a constant, coherent, and appealing dialogue, as current software is still far from being able to have natural everyday conversations with humans [3]. The chat approach is designed in such a way that it gives human users the impression that they are naturally chatting with another human. Chatbots can play an important role in the field of education because they are an interactive mechanism compared to traditional e-learning systems [4]. Among other ICTs, chatbots are considered safe and accessible learning tools that can bring positive results in learning. One of the reasons that chatbots are popular in various businesses is the increased efficiency of the process. This argument is also used in education as it increases user-student satisfaction by speeding up response times and can be available 24 h a day to answer or clarify any question [5]. This allows teachers, for example, to avoid answering repetitive questions that can be easily answered through chatbots, while also supporting students who have missed one or more lessons [6]. In addition to simply providing the question-answer function or exchanging information between students and the system, a chatbot contributes to tackling the problem of supporting/managing several individual student cases. During a lesson, the teacher usually does not have enough time for formative feedback to each individual student [5]. However, formative feedback during learning processes is, according to [PERSON] [7], one of the most important factors in increasing students' performance and motivation. AnAI chatbot has the ability to assist each student individually, following different learning spaces, to provide them with knowledge according to their individual cognitive level. In addition, chatbots seem to allow students to receive individual support in a bug-friendly environment, giving them the opportunity to apply their cognitive skills anytime and anywhere. This reduces stress and increases the willingness to learn [8]. Furthermore, a chatbot can be considered an excellent data analysis tool. [PERSON] and [PERSON] [9] state that it is important to remember that the teacher is the backbone of the teaching process, and that learning technology can act as an enhancer rather than a substitute. For example, when the chatbot is used to answer students' questions, the teacher can use the conversation logs and statistics reporting to see where the students are having problems and what their weaknesses are. Thus, the teacher can use this technology to look for problems, while students use it to solve them. Despite the aforementioned advantages, there are still communication problems between chatbots and humans. For example, limitations are found in the ability to correctly recognize natural language (especially in languages beyond English, such as Greek), difficulties in the flow of dialogue [10], inability to control repetitive sentences, and difficulty in dealing with unknown sentences [11]. Another disadvantage is that chatbots are often unable to answer complex or unexpected questions, as a result of which, they misinterpret what the student says and produce inappropriate dialogue flows [12]. This can result in student frustration, who will then seek other means of learning. Finally, chatbots are considered predictable, redundant, and have a bad memory, as they find it difficult to memorize previous conversations, forcing users to ask the same question repeatedly [13].