1. The subject of Theoretical Grammar. Different approaches to the analysis of l-ge phenomena. L. Incorporates the 3 constituent parts. These parts are the phonological system, the lexical system, the grammatical system. Only the unity of these 3 elements forms a l-ge. The phonological syst. determines the material (phonetical) appearance of its significative units. The lexical syst. is the whole set of naming means of l-ge, that is, w-ds and word-groups. The gr. syst. is the whole set of regularities determining the combination of naming means in the formation of utterances. Traditionally, grammar is determined as the syst. of rules of changing of the word and the rules and regulations of their combining in the sent. That is why it is divided into 2 parts: morphology (rules of word’s changing) and syntax (rules of word combining into sentences).The aim of theor. Gr. of the lang. is to present a theor. description of its gr. system, i.e. to scientifically analyze and define its gr. categories and study mechanisms of gr. formation of utterances out of words in the process of speech making. The nature of grammar as a constituent part of language is better understood in the light of explicitly discriminating the 2 planes of l-ge, namely, the plane of content and the plane of expression. The plane of content comprises the purely semantic elements contained in l-ge, while the plane of expression comprises the material (formal) units of l-ge taken by themselves, apart from meanings rendered by them. The 2 planes are inseparably connected, so that no meaning can be realized without some material means of expression. Gram. elements of l-ge present a unity of content and expression (a unity of form and meaning). In this the gr. elements are similar to the lingual lexical elements, though the quality of gr. meanings, as we have stated above, is different in principle from the quality of lexical meanings. On the other hand, the correspondence between the planes of content and expression is very complex, and it is peculiar to each language. This complexity is clearly illustrated by the phenomena of polysemy, homonymy and synonymy. Lingual units stand to one another in 2 fundamental types of relations: syntagmatic and paradigmatic. Syntagmatic relations are immediate linear relations between units in a segmental sequence. E.g.: The spaceship was launched without the help of a booster rocket. In this sentence syntagmatically connected are the words and word-groups the spaceship, was launched, the spaceship was launched, was launched without the help, the help of a rocket, a booster rocket. Paradigmatic relations coexist with syntagmatic relations in such a way that some sort of syntagmatic connection is necessary for the realization of any paradigmatic series. This is especially evident in a classical grammatical paradigm which presents a productive series of forms each consisting of a syntagmatic connection of two elements: one common for the whole of the series, the other specific for every individual form in the series. Grammatical paradigms express various grammatical categories. The minimal paradigm consists of 2 form-stages. This kind of paradigm we see, for instance, in the expression of the category of number: boy - boys. A more complex paradigm can be divided into component paradigmatic series, i.e. into the corresponding sub-paradigms. In other words, with paradigms, the same as with any other systemically organized material, macro- and micro-series are to be discriminated. Units of language are divided into segmental and supra-segmental. Segmental units consist of phonemes, they form phonemic strings of various status (syllables, morphemes). Supra-segmental units do not exist by themselves, but are realized together with segmental units and express different modificational meanings (functions) which are reflected on the strings of segmental units. To the supra-segmental units belong intonations (intonation contours), accents, pauses, patterns of word order. The segmental units of l-ge form a hierarchy of levels. This hierarchy is of a kind that units of any higher level are formed of units of the immediately lower level. Thus, morphemes are decomposed into phonemes, words are decomposed into morphemes, phrases are decomposed into words, etc. The lowest level of lingual segments is phonemic, it is formed by phonemes as the material elements of the higher-level segments. The phoneme has no meaning, its function is purely differential: it differentiates morphemes and words as material bodies. Since the phoneme has no meaning, it is not a sign. Units of all the higher levels of language are meaningful; they may be called "signemes" as opposed to "cortemes", i.e. non-meaningful units of different status, such as phonemes, syllables, and some others. The third level in the segmental lingual hierarchy is the level of words, or lexemic level. The word (lexeme), as different from the morpheme, is a directly naming (nominative) unit of l-ge: it names things and their relations. Since words are built up by morphemes, the shortest words consist of one explicit morpheme only. The next higher unit is the phrase, it is located at the phrasemic level. To level-forming phrase types belong combinations of 2 or more notional words. These combinations, like separate words,have a nominative function, but they represent the referent of nomination as a complicated phenomenon, be it a concrete thing, an action, a quality, or a whole situation. Then the level of sentences is located, or the proposemic level. The peculiar character of the sentence as a signemic unit of language consists in the fact that, naming a certain situation, or situational event, it expresses predication, i.e. shows the relation of the denoted event to reality. Namely, it shows whether this event is real or unreal, desirable or obligatory, stated as a truth or asked about, etc. In this sense, as different from the word and the phrase, the sentence is a predicative unit. The supra-proposemic construction is a combination of separate sentences forming a textual unity. In the typed text, the supra- sentential construction commonly coincides with the paragraph. The next level is the level of text which consists of a group of supra- sentential constructions. The highest level is the level of discourse. Discourse is interpret as a difficult communicative phenomenon which includes in itself social context, the information about participants, knowledge about the process production and perception of the text.