Junior technical university students who begin their studies through CLIL (Content and Language Integrated Learning) programs face a huge volume of general technical information. An introduction course is included in the mechanical engineering curriculum to guide students through the sea of professional knowledge and provide insight into their area of interest. The introduction into mechanical engineering includes classification and systematization in relation to: kinds of engineering activity, typical objects and elements included in objects, as well as operations with objects. Every element and object is part of the profession language, which includes terminological vocabulary. This vocabulary is multilingual for СLIL students, and developing it is a significant and challenging work. There are various options for constructing a vocabulary, including a conventional dictionary, a collocation dictionary, a thesaurus (a particular type of systematized dictionary), and others. Nouns, adjectives, and participles are the most common lexical elements used in these compendia to express terminology. This is useful for storing information, but it is insufficient for active use. Actions and operations that transform objects are very important in engineering practice. In linguistic terms, verbs convey these acts and procedures. It is nearly impossible to make an assertion based just on dictionary nouns. As a result, dictionary entries provide examples of phrases that use certain terms. Mind maps are an excellent approach to arrange vocabulary that might be actively used in engineering practice. One of the key benefits of mind maps is that they help to organize terminology logically. However, in order to account for the operational aspects of engineering tasks, a certain type of mental map is required. In our point of view, the most optimum mental maps are those that take the form of a graph, which is a set of related objects. The graph's vertices include nouns or parts of speech that are relevant to them. Verbs represent the graph's edges. The teaching method based on mental maps was tested on first-year CLIL students. The paper discusses both successful and poor mind maps made by students. The investigation demonstrated that the quality of mental maps is directly related to the comprehension of educational information and its application for text composition.

Keywords: Mind map, junior students, engineering, terminology, CLIL, graph, vocabulary.