The paper is devoted to the study of the cognitive function associated with the generation of elliptical sentences in the Russian language. The study is conducted by testing this cognitive ability using a computer system specially developed by the authors for this purpose. Testing of this cognitive ability is proposed and implemented for the first time. The system is an extension of Moodle and is openly hosted in the github repository. Elliptical constructions are limited to verbal and nominal ellipses, which are theoretically possible to be completely reconstructed based on the context of the sentence. The study is conducted with the participation of SPbPU students as respondents. The texts of planimetric tasks are chosen as the subject area. As a result of the analysis of testing data, the following results are obtained: the influence of the respondent’s knowledge of the subject area (planimetry) on the test results is established; a tendency towards self-study of respondents was discovered, which is manifested in a reduction in time and an increase in scores as they pass tests; it is shown that respondents are poorly motivated if they do not see feedback on the answer to the completed task. The paper discusses the problems of further development of the testing system and its use in adapting questionnaires (tasks) to assess the knowledge of SPbPU students in the field of automation of bug detection in programs, as well as for diagnosing the functional state of operator specialists and express diagnosis of dementia. It also seems promising to use the system to improve the processes of syntactic parsing of elliptic sentences and automate the restoration of ellipses in the subject area of planimetry.

Cognitive abilities cover all higher human intellectual functions, including oral and written speech. The use of ellipses in writing is associated with the ability to clearly formulate a thought, avoiding the redundancy of its expression. Testing the ability to use ellipses can be the basis, on the one hand, for assessing the cognitive operation of generating ellipses in writing and detecting violations of this operation. This can serve as the basis for the early detection of dementia in medicine. On the other hand, such testing can be used to teach speech technologies, including in foreign languages. From a scientific point of view, it is important to determine the influence degree of training on the performance of text tasks. The article describes the development of a computer system for remote on-line testing the operation of converting a complete sentence into a sentence with an ellipsis of a certain type, the principles of evaluating the results of testing the subjects. The concept of the system is discussed. The structure of system and software development environment are described. A feature of the system is the creation of a new type of tasks related to natural language processing. The complexity of the development is determined by the need for automated formation of a bank of sentences’ pairs in natural language without ellipses and with ellipses of a certain type, which entails the inclusion, in the software environment, of text parsing tools and algorithms for automated formation of ellipses and / or restoration of complete sentences from elliptical ones. In conclusion, the prospects for the development and application of the proposed system are discussed.