Theory of the Morphological Field:
In a group of words there are ones which have all indications (signs) of a definite morphological part of speech; there are also words which have not all indications (signs) of a definite morphological part of speech. The former form the nucleus of the morphological field of a certain part of speech; the latter – its periphery.
For example:
*The word table form the periphery of the Noun, not the nucleus, because it can, for example, have a sign of the Adjective. In the word-combination a big table it has a sign of the Noun but in the word-combination a table lamp – the one of the Adjective.
*Words like pen, woman, sky, etc. form the nucleus of the Noun. They always are main and attributed in word-combinations.
Two general tasks of linguists are:
1) to define the structure of the field and the composition of the language elements (words) in the morphological field of a part of speech;
2) to determine the indications which make some language elements close to another or other morphological parts of speech (ex. with table).