The position of the tongue. The position of the tongue in the mouth cavity is
characterized from two aspects, that is the horizontal and vertical movement.
According to the horizontal movement Soviet phoneticians distinguish 5 classes of
English vowels:
1)front [i
: , e, ei, æ,
ɛǝ
]
2)front-retracted [i, i
ǝ
]
3) central [
ʌ
,
ɜ
:,
ə
,
ɜ
u,
ɛ
u]
4) back [
ɒ
,
ɑ
:,
ɔ
:, u:]
5) back-advanced [u, u
ǝ
]
According to the vertical movement of the tongue the following 6 groups of
vowels are distinguished:
1. close a) narrow [i
: , u
:] b) broad [i, u, i
ə
, u
ə
]
2. mid a) narrow [e,
ɜ
:,
ə
, ei,
ɜ
u]
b) broad [
ə
,
ʌ
]
3. open a) narrow [
ɛə
,
ɔ
:,
ɔ
i
] b) broad [æ, ai, au,
ɑ
:,
ɒ
]
Lip position or lip rounding. Traditionally three lip positions are distinguished,
that is spread, neutral and rounded. For the purpose of classification vowels it is
sufficient to distinguish between two lip positions: rounded and unrounded, or
neutral.
Vowel length or quantity. Traditionally there are distinguished short and long
vowels (monophthongs). It is common knowledge that a vowel like any other sound
has physical duration – time which is required for its production (articulation). When
sounds are used in connected speech they cannot help being influenced by one
another. Duration is one of the characteristics of a vowel which is modified due to
various factors.
Tenseness. It characterizes the state of the organs of speech at the moment of
production of a vowel. Special instrumental analysis shows that historically long
vowels are tense while historically short vowels are lax.
