1. Introduction

The appearance of conversion in the English language is connected with some facts of the history of the English language.

The first •scientific definition of conversion was given still in the 1950’s by Prof. A.I. Smirnitsky: conversion is the formation of a new word solely through changes in the paradigm (paradigm is a set of gram­matical forms of this or that word proper to it as a part of speech). As the part of speech which is a morphological category is taken into consideration, this definition is morphological.

e.g.: taxi – to taxi, water – to water.

The difference in them is in the fact that they have different paradigms due to their belonging to different parts of speech: n taxi (sing), taxis (pl) – v to taxi, taxies, taxied, will taxi etc.

The modern definition of conversion combines the morphological definition and the change of function. As function in the language, or in the speech, is the problem of syntax, so the modern definition is morphologo-syntactical.

2. The Historical Development of Conversion

The causes that made conversion, this specific English way of word-building, appear, and become widespread are to be approached diachronically.

After the Scandinavian conquest, due to the fact that the conquerors and the conquered were people of the same origin, same cultural level, customs and traditions and their languages were akin, Scandinavians and Englishmen could easily communicate. The fact that the languages were akin made communication much easier for them: the roots as it happens to languages of the same origin were mostly alike and differences were in affixes and inflexions. While communicating the English and Scandinavians stressed the parts of words that were alike and neglected those which differed, so as we know in Middle English there began a 'levelling' of endings, one of the reasons of which was the Scandinavian conquest.

Old English lufian (v), lufu (n) –Modern English love (n, v),

More rarely it is the prefix that was dropped: Old English зemynd –Modern English mind.

Words borrowed from other languages underwent the same process, for example, French borrowings: Old French eschequier (v), eschec (n) –Modern English check (n, v).

Nowadays, new pairs of converted words are built on the analogy with those already in the word-stock: to phone, to wire, to can etc.

Prof. Yartseva considers it necessary to distinguish between homonymous word-pairs which appeared as a result of the loss of endings (she calls them cases of historical homonymy) and those formed on the analogy with those in the word-stock (she calls them cases of conversion proper). Prof. Smirnitsky is of the opinion that on a synchronic level there is no difference in correlation between such cases. He and Otto Jespersen consider that both cases should be united and called 'conversion' because their word-building foundation is the same. For practical purposes it is simpler and more convenient to use one and the same term lot both cases.

3. The Problem of the First Component in ‘Stone Wall’

In the theory of conversion, there exists the problem if the first component in word combinations of the 'stone wall' type (speech sound, rose garden, cannon ball, log cabin, price rise, etc.) is a noun in the function of an attribute or a converted adjective from a noun. In the latter case it would mean that conversion of nouns into adjectives is possible in English.

There are two points of view. Otto Jespersen and some other linguists consider that 'stone' is a converted adjective.

Prof. Yartseva, Prof. Ilyish, Prof. Zhigadlo and the English linguist Henry Sweet consider that 'stone' is a noun in the function of an attribute. They say that 'stone' is characteristic of English as it is poor in morphological forms.

The problem is not solved yet.