1. Grammatical category and its characteristic features.
M.Y. Blokh defines the grammatical category as "a system of expressing a generalized grammatical meaning by means of paradigmatic correlation of grammatical forms". The forms united into a grammatical category possess a common general meaning that gives a name to the category and each form possesses its own specific meaning that presents a specification of the general meaning and differentiates the form from the other form/forms within the category. The forms lives - lived - will live are united on the basis of the common general grammatical meaning of tense and constitute the grammatical category of tense. Within this category each form has its own specific meaning of tense: present, past and future. The grammatical category of tense presents 'a specific lingual expression of objective (ontological) time, the grammatical category of case presents various relations between the action and its participants, the grammatical category of number in nouns reflects the quantitative relations between homogeneous objects of reality, the grammatical category of mood presents the relations between the action and reality as they are presented by the speaker etc. Such grammatical categories may also be called inherent. Conceptual grammatical categories are universal, they exist in most of the languages though their volume and their scope may vary considerably in various languages. The grammatical category of number is the most universal grammatical category, all speech communities have linguistic means of encoding number, though these means differ greatly in different languages.
A grammatical category is constituted on the basis of contrastive grammatical forms which share a certain grammatical meaning correlated to some general concept (time, number) and differ in more concrete meanings within the scope of the same concept. Such contrastive grammatical forms are called oppositions and all grammatical categories are based on oppositions. The method of oppositional analysis was introduced by Trubetskoy who applied it to the study of phonemes. Now the method of oppositional analysis is widely used in lexicology and grammar.