The article examines a set of issues related to the features of the classification of signs of oral speech for various diagnostic and evaluation criteria:
– by their stability / instability;
– by their origin (congenital / acquired);
– by their nature (dynamic / static);
– according to the form of implementation (materially expressed / hidden);
– according to their functional purpose (monofunctional / multifunctional);
– by their composition (simple / complex / complex /;
– by their classification significance (general / private);
– by frequency of implementation in speech, etc.
All listed classification groups of signs are described both in the content plan and in the functional one, that is, the features of their identification, evaluation of the factors under the influence of which they formed and the evaluation of their diagnostic and identification significance are analyzed. Such an approach to their study is due to the fact that the possibility of correlating a trait with a particular area of scientific knowledge is not always obvious and unambiguous. Different properties of the human person can be realized in his speech in the form of one and the same sign. For example, a more closed version of the pronunciation of sound [a] can manifest itself as an individual feature of the articulation of a particular person, as a sign of speech in a non-native language or a dialect feature (a common sign that is studied in the framework of sociolinguistics, psycholinguistics and linguistics), as a sign of imitation which is studied in the framework of psycholinguistics, sociolinguistics, linguistics), as an accidental (unstable) feature, the manifestation of which is due to the physical state of the speaker, nicative situation (eating, jogging in the process of speaking), etc. Therefore, understanding the nature of the origin and realization of a particular sign in speech is a fundamental condition for its correct classification, on the basis of which an objective assessment of its diagnostic and identification significance is subsequently achieved in the complex of signs of a particular person’s speech and, consequently, of his forming expert conclusions.
The article also outlines the principles for the classification of signs according to their composition by dividing them into three groups: simple signs, complex and complex. Particular attention is paid to complex features (for example, signs of cross-language interference), which consist of simple signs and are established after analyzing the signs of the components. As a result, complex signs are often not fully investigated, which can lead to the bias of the expert’s conclusions.
Key words: linguistic study of oral speech, diagnostic analysis, idiolect, classification, sign, evaluation of the significance of the sign, complex of signs, persistent sign, intensity of manifestation of signs, interlingual interference, level of linguistic research.