Vowels

We shall first have a closer look at the way in which vowels differ from consonants.

Then we shall analyse vowels phonetically, i.e. according to:

- tongue position: how high in the mouth is the tongue, and which part of the tongue

is the highest?

- length: are the vowels long or short?

- rounding: are the lips rounded or not?

- nasality: is there free passage of air through the nose?

- diphthongs: are they steady, or do they somehow change in character?

Difference from Consonants

Even though all the languages of the world contain both vowels and consonants, and

although almost everybody has some idea of whether a given sound is a vowel or a

consonant in his language, there is actually more than one way to distinguish between the

two classes of sounds. From a phonetic point of view one way of distinguishing is by

considering which sounds have the highest degree of obstruction. Although vowels have

almost no obstruction, and some consonants (obstruents, nasals, and the lateral) have a high

degree of obstruction, there is a group of consonants (the approximants) which would be

classified as vowels if this criterion was used: approximants have no more obstruction than

vowels. This can be seen by comparing the approximant [j] in yeast [ji:st]with the vowel [i:]

in east [i:st].

From a phonological point of view, it is possible to distinguish between vowels and

consonants by testing which sounds may be the nucleus of a syllable, i.e. the part of a syllabe

that cannot be left out. If you consider a syllable such as [k@:t] cart, the initial [k] may be left

out and we still have a syllable, [@:t] art, the final [t] may be left out and we still have a

syllable , [k@:] car. In fact [k] and [t] may both be left out, and the remainder is still a

syllable, [@:] are. If however you try to leave out the vowel, then there is no syllable

anymore:* [kt]. [ a:] is then the sound that cannot be left out. Compare with yeast whereas

[j] can be left out, giving [i:st], [i:] can’t:*[jst]. Syllabicity seems to be the criterion to

determine whether a sound is a vowel or a consonant.

The above discussion would not be complete if we didn't mention the problem of socalled

syllabic consonants. This is the case when sounds like / r,l,n / may function as a

separate syllable consisting of an only sound, as in /kPt+n/ cotton or /zp+l/ apple, where

English speakers clearly hear two separate syllables. In these words, the /n/ and /l/ seem to

function as the nucleus of the second syllable of these words. However they cannot be

classified as vowels, as they can never occur alone as a word. 

 Tongue Position

Tongue position is described using two criteria: the height (how high is the tongue)

and the part of the tongue involved in the production of the sound.

In English the tongue may either be high, i.e. when the speaker produces e.g. [i:, u:]

in [bi:t, bu:t] beat, boot, intermediate, e.g. [e,N:] in [bet, bN:t] bet, bought, or low, e.g.

[z,a:] in [bzt, ba:t] bat, Bart.

a) tongue is at the highest b) tongue is at the lowest

Depending on the language we can have several intermediate tongue heights. English

has three heights: high, mid and low, whereas French has two intermediate tongue heights

with a total of four tongue heights: high, mid high, mid low and low.