R. S. Ginzburg, S. S. Khidekel, G. Y. Knyazeva, A. A. Sankin a course in modern english

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By means of vowel-interchange we distinguish different parts of speech, e.g. full — to fill, food — to feed, blood — to bleed, etc. In some cases vowel-interchange is combined with affixation, e.g. long — length, strong — strength, broad — breadth, etc. Intransitive verbs and the corresponding transitive ones with a causative meaning also display vowel-interchange, e. g. to rise — to raise, to sit — to set, to lie — to lay, to fall — to fell.

The type of consonant-interchange typical of Modern English is the interchange of a voiceless fricative consonant in a noun and the corresponding voiced consonant in the corresponding verb, e.g. use — to use, mouth — to mouth, house — to house, advice — to advise, etc.

There are some particular cases of consonant-interchange: [k] — [t∫]: to speak — speech, to break — breach; [s] — [d]: defence — to defend; offence — to offend; [s] — [t]: evidence — evident, importance — important, etc. Consonant-interchange may be combined with vowel-interchange, e.g. bath — to bathe, breath — to breathe, life — to live, etc.

Many English verbs of Latin-French origin are distinguished from the corresponding nouns by the position of stress. Here are some well-known examples of such pairs of words: ´export n — to ex´port v; ´import n — to im´port v; ‘conduct n — to con'duct v; ‘present n — to pre’sent v; ´contrast n — to con´trast v; ´increase n — to in´crease v, etc.

Stress-interchange is not restricted to pairs of words consisting of a noun and a verb. It may also occur between other parts of speech, for instance, between adjective and verb, e.g. ´frequent a — to fre´quent v; ´absent a — to ab´sent v, etc.