Conversion.

Some British historians write that one of the practical qualities of English is that " it has a grammar of great simplicity-простота and flexibility-гибкость. Nouns and adjectives have highly simplified word-endings.. Nouns can become verbs and verbs nouns in a way that it is impossible in other languages"

Conversion as a term refers to the cases of formal identity-одинаковость of words that belong to different parts of speech.

Conversion is usually restricted(ограничена) to words containing a single morpheme, although there are exceptions – cases like refer-ee (N → V).

There are rules limiting the freedom of forming new words, especially verbs, by means of conversion. Very rarely new verbs are created when a word with the same meaning already exists.

e. g. to shelve books, butnever to hospital the patient (Cf. to hospitalize).

. But there is the restriction consists in the following: one cannot create new verbs from words denoting points in time, though it is possible with the expressions denoting periods of time.

In such languages as English where inflexions are not numerous or there are no inflexions at all this process is extremely developed embracing practically all parts of speech.

There are at least two points of view on the abovementioned phenomenon. The syntactic (or functional) approach consists in the following: in pairs to walk – walk or to knife – knife the elements are forms of one and the same word, they differ in their syntactic function. Thus, a word can enter different parts of speech at a time, and what part of speech it refers to we can define only when it is used in speech.

Opinions differ on the possibility of nouns to become adjectives. This problem is called the 'stone wall' problem. The question that arises here is whether the first element in such combinations is a noun or an adjective? Approaching the problem morphologically we can say that the element stone is an adjective derived from the corresponding noun stone, and as an adjective it has acquired some adjectival characteristics: the lexico-grammatical meaning of an attribute of a substance, combinability. As for the paradigm, it seems to be impossible to form degrees of comparison of the relative adjective stone, nor is it possible to use it predicatively: the wall is stone*. Thus, adjectival nouns lie on the border-line between adjectives and nouns.

In English where there is lack of word-building morphemes the opposite process – that of substantivization of adjectives – takes place. One can differentiate between two types of substantivized adjectives:

a) fully converted adjectives which acquire all the characteristic features of nouns: they can be associated with articles and modified by an adjective, have the plural ending and the possessive case with -'s:

e. g. a native

an old native

the native

two natives

the native's hat;

b) partially substantivized adjectives which have developed the ability to attach the definite article, but they cannot take the plural ending, attach the indefinite article and have the possessive form:

e. g. the poor

the rich.