6.3. The Diphthong theory

If vowels are analysed on the basis of the stability of the articulation, they may be divided into monophthongs and diphthongs. Diphthongs are usually defined as vowels consisting of two distinct elements forming one syllable: the two elements are closely blended with one another.

All phoneticians agree that there are two kinds of diphthongs: falling and rising diphthongs. The first is more common in European languages; thus diphthongs of this type are usually considered true diphthongs, while rising diphthongs are considered false ones.

O. Jespersen distinguishes:

1) falling diphthongs which are true;

2) rising diphthongs which are false; and

3) level diphthongs (those in which it is difficult to decide whether the first or the second element is syllabic).

L. V. Scerba also differentiates between true and false diphthongs, but in his opinion a true diphthong is a monosyllabic combination of two vowels which are equally sonorous. This type of diphthong is rather rare, but it occurs in some languages. It can be found in the Lettish language, for instance, where [ie], [uo] are true diphthongs, e. g. piena, ruoka.

According to L. V. Scerba, there is only one type of true diphthong, but two types of false diphthongs: the falling and the rising type, the former being mare common in all languages. Besides these, there are monophthongs with a foreglide or with an afterglide that Scerba calls “diphthongoids”. The Russian /o/ phoneme and /e/ phoneme are samples of “diphthongoids”. They begin with a closer foreglide, thus /o/ is preceded by an [у] –foreglide, /e/ by an [u] –foreglide.

The type of vowels that Scerba calls “diphthongoids” might sooner be termed “imperfect diphthongs”, they cannot be called diphthongs in the true sense of this word.

D. Jones gives the following definition of a diphthong: “a diphthong is defined as an independent vowel glide not containing within it self either a peak or a “trough” of prominence. He also distinguished between short and long diphthongs, glide or narrow diphthongs.

He also speaks about an “imperfect” diphthong, which is not the same as L. V. Scerba’s “diphthongoid”, but is defined as follows: “Another kind of diphthong, called an imperfect diphthong, is produced (1) when the initial vowel of a falling diphthong is appreciably lengthened before the glide begins, or (2) when the final vowel of a diphthong (falling or rising) is lengthened after the glide ends. For example: the second element of [u] is lengthened in uttering the interjection “oh”.

Some of these statements are open to argument. If the initial vowel of a falling diphthong can be lengthened, the final element of a falling diphthong cannot. If it could be lengthened, it would lose its indistinct character and the diphthong would cease to be falling; it would become true in the sense of Scerba’s diphthong theory, it would not be falling, but leveled.

Questions

1) Comment on the problem of the distinction between vowels and consonants. Consider different points of view.

2) What differences are there between V and C?

3) Explain the essence of:

. a) articulatory differences between V and C

. b) acoustic differences between V and C

. c) functional differences between V and C.

4) What are the general principles of vowel articulation?

5) What criteria are used for the classification of vowels?

6) What are English vowels subdivided into?

7) Define diphthongs.

8) From what aspects is the position of the tongue in the mouth cavity characterized?

9) What groups of vowels are distinguished in English?

10) What are the traditional lip positions in English pronunciation?

11) What does the checkness of English vowel sounds depend on?

12) What is duration of a vowel modified by and what does it depend on?

13) Define tenseness.

14) What is the phonemic status of the neutral sound []?

15) Are all the vowel phonemes equally free in their distribution?

16) The English vowels can be met in alternation series, cannot they?

17) What kinds of diphthongs are distinguished in the English language?

Consider different points of view.