1. Grammatical category. Synthetical and analytical grammatical forms.

A grammatical category is a class of units (such as noun and verb) or features (such as number and case) that share a common set of grammatical properties. The term "grammatical category" refers to specific properties of a word that can cause that word and/or a related word to change in form for grammatical reasons (ensuring agreement between words).

For example, the word "boy" is a noun. Nouns have a grammatical category called "number". The values of number are singular (one) and plural (two or more).

The boy is playing.

The boys are playing.

English has over twenty grammatical categories. But some of grammatical categories are number, case, gender, person, tense, aspect, mood, voice and degree.

Grammatical forms can be morphemes, synthetic forms, and grammatical word combinations, which are analytical forms. Synthetic forms unite both lexical and grammatical meanings in one word. In analytical forms there two or more words in which at least one element is an auxiliary. The auxiliary is a constant element of an analytical structure, which is devoid of lexical meaning (it renders grammatical meanings and is a purely grammatical element). Analytical structures must be differentiated from free syntactical word combinations. In free syntactical word combinations all the elements possess both lexical and grammatical meanings.

Cf. waiter and waitress

The distinctions of gender in Russian are universal. They refer to all the vocabulary of the language. In English this distinction is not a grammatical phenomenon. The grammatical category of gender is lost. What we have now is some gender distinctions existing as the remnant of history. The distinction “waiter vs. waitress” is not universal enough to build up a grammatical category. It does not possess the level of grammatical abstraction characterized by an unlimited range of occurrence.

Cf. book and books

-s is a form-building morpheme that builds a grammatical form because it is characterized by the level of grammatical abstraction realized in an unlimited range of occurrence.

2. Principles of dividing words into parts of speech.

The words of the language, depending on various formal and semantic features, are divided into grammatically relevant sets of classes. Parts of speech are lexico-grammatical categories of words. The term was introduced in ancient Greece, where there was no strict differentiation between the word as a vocabulary unit and the word as a functional element of the sentence.

In modern linguistics, parts of speech are discriminated on the basis of the three criteria: semantic, formal, and functional. The semantic criterion is based on evaluation of the generalized meaning, categorial meaning of the part of speech (noun-things). Words are corelated with classes of reality. The formal criterion is based on the specific word-building features (-ness, -tion – nouns) and paradigmatic sets (-s, ‘s – nouns). The functional criterion concerns the syntactic role of words in the sentence typical of a part of speech or methods of combining with other words in the phrase. For example, verb combines with a noun (write a letter), with an adverb (write quickly) and in the sentence functions as a predicate. The said three factors of categorial characterization of words are referred to as, respectively, meaning, form, and function.

Meaning (Semantic Properties)

Each part of speech is characterized by the general meaning which is an abstraction from the lexical meanings of constituent words. (The general meaning of nouns is substance, the general meaning of verbs is process, etc.) This general meaning is understood as the categorial meaning of a class of words, or the part-of-speech meaning. Semantic properties of a part of speech find their expression in the grammatical properties. To sleep, a sleep, sleepy, asleep refer to the same phenomenon of objective reality, but they belong to different parts of speech, as their grammatical properties are different. So meaning is a supportive criterion which helps to check the purely grammatical criteria, those of form and function.

Form (Morphological Properties)

The formal criterion concerns the inflexional and derivational features of words belonging to a given class, i.e. the grammatical categories (the paradigms) and derivational (stem-building, lexico-grammatical) morphemes. This criterion is not always reliable as many words are invariable and many words contain no derivational affixes. Besides, the same derivational affixes may be used to build different parts of speech: -ly can end an adjective, an adverb, a noun: a daily; -tion can end a noun and a verb: to position. Because of the limitation of meaning and fonn as criteria we mainly rely on a word's function as a criterion of its class.

Function (Syntactic Properties)

Syntactic properties of a class of words are the combinability of words (the distributional criterion) and typical functions in the sentence. The three criteria of defining grammatical classes of words in English may be placed in the following order: function, form, meaning. Parts of speech are heterogeneous classes and the boundaries are not clearly cut especially in the area of meaning. Within a part of speech there are subclasses which have all the properties of a given class and subclasses which have only some of these properties and may have features of another class. So a part of speech may be described as a field which includes both central, most typical members, and marginal, less typical members. Marginal areas of different parts of speech may overlap and there may be intermediary elements with contradictory features (statives, modal words, pronouns). Words belonging to different parts of speech may be united by a common feature and constitute a class cutting across other classes (f. ex., determiners). So the part-of-speech classification involves overlapping criteria and scholars single out from 9 to 13 parts of speech in Modern English.